0000950170-25-098559 | 20-F | XBRL Viewer | OMS Energy Technologies INC

Financial Instruments - Summary of Effect of Changes in Foreign Exchange Rates (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Foreign Currency Exposure [Line Items]
Sensitivity of foreign currency	$ 636	$ 419

Document and Entity Information	12 Months Ended
Document and Entity Information	Mar. 31, 2025 shares
Document Information [Line Items]
Document Type	20-F
Amendment Flag	false
Document Registration Statement	false
Document Annual Report	true
Current Fiscal Year End Date	--03-31
Document Period End Date	Mar. 31, 2025
Document Fiscal Year Focus	2025
Document Fiscal Period Focus	FY
Document Transition Report	false
Document Shell Company Report	false
Entity File Number	001-42638
Entity Registrant Name	OMS Energy Technologies Inc.
Entity Central Index Key	0002012219
Entity Incorporation, State or Country Code	E9
Entity Address, Address Line One	10 Gul Circle
Entity Address, City or Town	Singapore
Entity Address, Country	SG
Entity Address, Postal Zip Code	629566
Title of 12(b) Security	Ordinary Shares, par value $0.0001 per share
Trading Symbol	OMSE
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Common Stock, Shares Outstanding	38,745,000
Entity Filer Category	Non-accelerated Filer
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Document Accounting Standard	International Financial Reporting Standards
Entity Shell Company	false
Auditor Name	Marcum Asia CPAs LLP
Auditor Firm ID	5395
Auditor Location	New York, New York
Business Contact [Member]
Document Information [Line Items]
Contact Personnel Name	Cogency Global Inc.
Entity Address, Address Line One	122 East 42nd Street, 18th Floor
Entity Address, State or Province	NY
Entity Address, City or Town	New York
Entity Address, Postal Zip Code	10168
City Area Code	+800
Local Phone Number	211-0102

Label	Element	Value
Increase (decrease) through payment of lease liabilities arising from financing activities	omse_IncreaseDecreaseThroughPaymentOfLeaseLiabilitiesArisingFromFinancingActivities	$ 0
Increase (decrease) through payment of lease liabilities arising from financing activities	omse_IncreaseDecreaseThroughPaymentOfLeaseLiabilitiesArisingFromFinancingActivities	(824,000)
Increase (decrease) through payment of lease liabilities arising from financing activities	omse_IncreaseDecreaseThroughPaymentOfLeaseLiabilitiesArisingFromFinancingActivities	(824,000)
Increase (decrease) through payment of lease liabilities arising from financing activities	omse_IncreaseDecreaseThroughPaymentOfLeaseLiabilitiesArisingFromFinancingActivities	0
Increase (decrease) through payment of lease liabilities arising from financing activities	omse_IncreaseDecreaseThroughPaymentOfLeaseLiabilitiesArisingFromFinancingActivities	(1,302,000)
Increase (decrease) through payment of lease liabilities arising from financing activities	omse_IncreaseDecreaseThroughPaymentOfLeaseLiabilitiesArisingFromFinancingActivities	(1,302,000)
Increase (decrease) through payment of lease liabilities arising from financing activities	omse_IncreaseDecreaseThroughPaymentOfLeaseLiabilitiesArisingFromFinancingActivities	0
Increase (decrease) through payment of lease liabilities arising from financing activities	omse_IncreaseDecreaseThroughPaymentOfLeaseLiabilitiesArisingFromFinancingActivities	0
Increase (decrease) through payment of lease liabilities arising from financing activities	omse_IncreaseDecreaseThroughPaymentOfLeaseLiabilitiesArisingFromFinancingActivities	(197,000)
Increase (decrease) through payment of lease liabilities arising from financing activities	omse_IncreaseDecreaseThroughPaymentOfLeaseLiabilitiesArisingFromFinancingActivities	(197,000)
Termination of lease liabilities	omse_TerminationOfLeaseLiabilities	0
Termination of lease liabilities	omse_TerminationOfLeaseLiabilities	(1,153,000)
Termination of lease liabilities	omse_TerminationOfLeaseLiabilities	(1,153,000)
Termination of lease liabilities	omse_TerminationOfLeaseLiabilities	0
Termination of lease liabilities	omse_TerminationOfLeaseLiabilities	(1,599,000)
Termination of lease liabilities	omse_TerminationOfLeaseLiabilities	$ (1,599,000)
Capital Contribution Shares	omse_CapitalContributionShares	12,756,000
Zakat Liability	omse_ZakatLiability	$ 15,000.000
Net change in inventories	omse_NetChangeInInventories	82,006,000
Net change in inventories	omse_NetChangeInInventories	65,104,000
Net change in inventories	omse_NetChangeInInventories	5,348,000
Net change in inventories	omse_NetChangeInInventories	$ 43,122,000
Trade Payable Settlement Term	omse_TradePayableSettlementTerm	30 days
Trade Payable Settlement Term	omse_TradePayableSettlementTerm	90 days
Changes In Operating Assets And Liabilities	omse_ChangesInOperatingAssetsAndLiabilities	$ 51,653,000
Changes In Operating Assets And Liabilities	omse_ChangesInOperatingAssetsAndLiabilities	30,969,000
Changes In Operating Assets And Liabilities	omse_ChangesInOperatingAssetsAndLiabilities	(2,112,000)
Changes In Operating Assets And Liabilities	omse_ChangesInOperatingAssetsAndLiabilities	$ 29,529,000
Other Payables Average Term	omse_OtherPayablesAverageTerm	30 days
Other Payables Average Term	omse_OtherPayablesAverageTerm	90 days
Deferred tax assets net operating loss carryforwards	omse_DeferredTaxAssetsNetOperatingLossCarryforwards	$ 0
Deferred tax assets net operating loss carryforwards	omse_DeferredTaxAssetsNetOperatingLossCarryforwards	0
Additional Tax Liability	omse_AdditionalTaxLiability	2,300,000
Allowance For Expected Credit Losses	omse_AllowanceForExpectedCreditLosses	124,000
Allowance For Expected Credit Losses	omse_AllowanceForExpectedCreditLosses	3,000
Allowance For Expected Credit Losses	omse_AllowanceForExpectedCreditLosses	6,000
Allowance For Expected Credit Losses	omse_AllowanceForExpectedCreditLosses	6,000
Tax adjustment of previous years amount	omse_TaxAdjustmentOfPreviousYearsAmount	902,000
Tax adjustment of previous years amount	omse_TaxAdjustmentOfPreviousYearsAmount	(1,156,000)
Tax adjustment of previous years amount	omse_TaxAdjustmentOfPreviousYearsAmount	(229,000)
Additional Tax And Zakat Payable From Tax Assessment	omse_AdditionalTaxAndZakatPayableFromTaxAssessment	$ 580,000
Number of shares acquired	omse_NumberOfSharesAcquired	102,756,000
Repayment of loans due to former related party	omse_RepaymentOfLoansDueToFormerRelatedParty	$ (3,000,000)
Repayment of loans due to former related party	omse_RepaymentOfLoansDueToFormerRelatedParty	(3,000,000)
Payment Of Additional Tax Liability	omse_PaymentOfAdditionalTaxLiability	2,300,000
Tax Paid Arise from Tax Assessment	omse_TaxPaidAriseFromTaxAssessment	580,000
Deferred tax assets not recognized amount	omse_DeferredTaxAssetsNotRecognizedAmount	6,000
Deferred tax assets not recognized amount	omse_DeferredTaxAssetsNotRecognizedAmount	17,000
Other income/(expenses), net	omse_OtherIncomeExpensesNet	246,000
Other income/(expenses), net	omse_OtherIncomeExpensesNet	50,204,000
Other income/(expenses), net	omse_OtherIncomeExpensesNet	(79,000)
Other income/(expenses), net	omse_OtherIncomeExpensesNet	(7,000)
Provision for Outstanding Tax Dispute	omse_ProvisionForOutstandingTaxDispute	2,300,000
Provision for Outstanding Tax Dispute	omse_ProvisionForOutstandingTaxDispute	1,700,000
Increase (decrease) through changes in Interest Expense Related To Liabilities Arising From Financing Activities	omse_IncreaseDecreaseThroughChangesInInterestExpenseRelatedToLiabilitiesArisingFromFinancingActivities	757,000
Increase (decrease) through changes in Interest Expense Related To Liabilities Arising From Financing Activities	omse_IncreaseDecreaseThroughChangesInInterestExpenseRelatedToLiabilitiesArisingFromFinancingActivities	125,000
Increase (decrease) through changes in Interest Expense Related To Liabilities Arising From Financing Activities	omse_IncreaseDecreaseThroughChangesInInterestExpenseRelatedToLiabilitiesArisingFromFinancingActivities	882,000
Increase (decrease) through changes in Interest Expense Related To Liabilities Arising From Financing Activities	omse_IncreaseDecreaseThroughChangesInInterestExpenseRelatedToLiabilitiesArisingFromFinancingActivities	32,000
Increase (decrease) through changes in Interest Expense Related To Liabilities Arising From Financing Activities	omse_IncreaseDecreaseThroughChangesInInterestExpenseRelatedToLiabilitiesArisingFromFinancingActivities	221,000
Increase (decrease) through changes in Interest Expense Related To Liabilities Arising From Financing Activities	omse_IncreaseDecreaseThroughChangesInInterestExpenseRelatedToLiabilitiesArisingFromFinancingActivities	253,000
Increase (decrease) through changes in Interest Expense Related To Liabilities Arising From Financing Activities	omse_IncreaseDecreaseThroughChangesInInterestExpenseRelatedToLiabilitiesArisingFromFinancingActivities	162,000
Increase (decrease) through changes in Interest Expense Related To Liabilities Arising From Financing Activities	omse_IncreaseDecreaseThroughChangesInInterestExpenseRelatedToLiabilitiesArisingFromFinancingActivities	5,000
Increase (decrease) through changes in Interest Expense Related To Liabilities Arising From Financing Activities	omse_IncreaseDecreaseThroughChangesInInterestExpenseRelatedToLiabilitiesArisingFromFinancingActivities	24,000
Increase (decrease) through changes in Interest Expense Related To Liabilities Arising From Financing Activities	omse_IncreaseDecreaseThroughChangesInInterestExpenseRelatedToLiabilitiesArisingFromFinancingActivities	191,000
Effect Of Changes In Foreign Exchange Rates	omse_EffectOfChangesInForeignExchangeRates	84,000
Effect Of Changes In Foreign Exchange Rates	omse_EffectOfChangesInForeignExchangeRates	84,000
Effect Of Changes In Foreign Exchange Rates	omse_EffectOfChangesInForeignExchangeRates	(114,000)
Effect Of Changes In Foreign Exchange Rates	omse_EffectOfChangesInForeignExchangeRates	(114,000)
Effect Of Changes In Foreign Exchange Rates	omse_EffectOfChangesInForeignExchangeRates	0
Effect Of Changes In Foreign Exchange Rates	omse_EffectOfChangesInForeignExchangeRates	0
Effect Of Changes In Foreign Exchange Rates	omse_EffectOfChangesInForeignExchangeRates	136,000
Effect Of Changes In Foreign Exchange Rates	omse_EffectOfChangesInForeignExchangeRates	136,000
Additional Cash Payment To Associates	omse_AdditionalCashPaymentToAssociates	800,000
Additional Cash Payment To Associates	omse_AdditionalCashPaymentToAssociates	800,000
Current Trade Receivables Including Allowance For Expected Credit Losses	omse_CurrentTradeReceivablesIncludingAllowanceForExpectedCreditLosses	13,591,000
Current Trade Receivables Including Allowance For Expected Credit Losses	omse_CurrentTradeReceivablesIncludingAllowanceForExpectedCreditLosses	$ 31,951,000
Transactions with Owners of the Company Shares	omse_TransactionsWithOwnersOfTheCompanyShares	1,845,000
Transactions with Owners of the Company Shares	omse_TransactionsWithOwnersOfTheCompanyShares	1,845,000
Transactions with Owners of the Company Shares	omse_TransactionsWithOwnersOfTheCompanyShares	12,756,000
Transactions with Owners of the Company Shares	omse_TransactionsWithOwnersOfTheCompanyShares	1,845,000
Supplies and subcontracting costs	omse_SuppliesAndSubcontractingCosts	$ 17,991,000
Supplies and subcontracting costs	omse_SuppliesAndSubcontractingCosts	17,737,000
Supplies and subcontracting costs	omse_SuppliesAndSubcontractingCosts	2,701,000
Supplies and subcontracting costs	omse_SuppliesAndSubcontractingCosts	2,412,000
Allowance for (reversal of) expected credit losses	omse_AllowanceForReversalOfExpectedCreditLosses	(121,000)
Allowance for (reversal of) expected credit losses	omse_AllowanceForReversalOfExpectedCreditLosses	3,000
Allowance for (reversal of) expected credit losses	omse_AllowanceForReversalOfExpectedCreditLosses	$ 11,000
Shares Issued in Conversion of Convertible Note	omse_SharesIssuedInConversionOfConvertibleNote	750
Shares Issued in Conversion of Convertible Note	omse_SharesIssuedInConversionOfConvertibleNote	750
Impact of different tax rate in other jurisdiction amount	omse_ImpactOfDifferentTaxRateInOtherJurisdictionAmount	$ 2,209,000
Impact of different tax rate in other jurisdiction amount	omse_ImpactOfDifferentTaxRateInOtherJurisdictionAmount	(6,865,000)
Impact of different tax rate in other jurisdiction amount	omse_ImpactOfDifferentTaxRateInOtherJurisdictionAmount	109,000
Impact of different tax rate in other jurisdiction amount	omse_ImpactOfDifferentTaxRateInOtherJurisdictionAmount	539,000
Cash, Cash Equivalents And Cash Restricted Cash	omse_CashCashEquivalentsAndCashRestrictedCash	45,430,000
Cash, Cash Equivalents And Cash Restricted Cash	omse_CashCashEquivalentsAndCashRestrictedCash	29,903,000
Cash, Cash Equivalents And Cash Restricted Cash	omse_CashCashEquivalentsAndCashRestrictedCash	31,803,000
Cash, Cash Equivalents And Cash Restricted Cash	omse_CashCashEquivalentsAndCashRestrictedCash	18,580,000
Cash, Cash Equivalents And Cash Restricted Cash	omse_CashCashEquivalentsAndCashRestrictedCash	$ 75,831,000
Related Party Transactions Amount Receivable Settlement Period	omse_RelatedPartyTransactionsAmountReceivableSettlementPeriod	30 days
Related Party Transactions Amount Receivable Settlement Period	omse_RelatedPartyTransactionsAmountReceivableSettlementPeriod	60 days
Tax effect on change in valuation allowance	omse_TaxEffectOnChangeInValuationAllowance	$ 651,000
Liability-related other changes	omse_Liability-RelatedOtherChanges	757,000
Liability-related other changes	omse_Liability-RelatedOtherChanges	(968,000)
Liability-related other changes	omse_Liability-RelatedOtherChanges	(211,000)
Liability-related other changes	omse_Liability-RelatedOtherChanges	32,000
Liability-related other changes	omse_Liability-RelatedOtherChanges	6,222,000
Liability-related other changes	omse_Liability-RelatedOtherChanges	6,254,000
Liability-related other changes	omse_Liability-RelatedOtherChanges	162,000
Liability-related other changes	omse_Liability-RelatedOtherChanges	5,000
Liability-related other changes	omse_Liability-RelatedOtherChanges	(112,000)
Liability-related other changes	omse_Liability-RelatedOtherChanges	55,000
Cash Payment For Management Buyout	omse_CashPaymentForManagementBuyout	2,000,000
Deferred offering costs noncurrent	omse_DeferredOfferingCostsNoncurrent	981,000
Deferred offering costs noncurrent	omse_DeferredOfferingCostsNoncurrent	417,000
Derecognition Of Equity Method Investments Upon Disposal Of Associates	omse_DerecognitionOfEquityMethodInvestmentsUponDisposalOfAssociates	0
Derecognition Of Equity Method Investments Upon Disposal Of Associates	omse_DerecognitionOfEquityMethodInvestmentsUponDisposalOfAssociates	0
Derecognition Of Equity Method Investments Upon Disposal Of Associates	omse_DerecognitionOfEquityMethodInvestmentsUponDisposalOfAssociates	(10,773,000)
Freight charges	omse_FreightCharges	9,494,000
Freight charges	omse_FreightCharges	9,128,000
Freight charges	omse_FreightCharges	447,000
Freight charges	omse_FreightCharges	2,603,000
Goods And Services Tax Receivable Net	omse_GoodsAndServicesTaxReceivableNet	18,000
Loans And Borrowings Arising From Financing Activities Ending Balance	omse_LoansAndBorrowingsArisingFromFinancingActivitiesEndingBalance	874,000
Increase (decrease) in payment of interest arising from financing activities	omse_IncreaseDecreaseInPaymentOfInterestArisingFromFinancingActivities	(98,000)
Increase (decrease) in payment of interest arising from financing activities	omse_IncreaseDecreaseInPaymentOfInterestArisingFromFinancingActivities	(125,000)
Increase (decrease) in payment of interest arising from financing activities	omse_IncreaseDecreaseInPaymentOfInterestArisingFromFinancingActivities	(223,000)
Increase (decrease) in payment of interest arising from financing activities	omse_IncreaseDecreaseInPaymentOfInterestArisingFromFinancingActivities	(32,000)
Increase (decrease) in payment of interest arising from financing activities	omse_IncreaseDecreaseInPaymentOfInterestArisingFromFinancingActivities	(221,000)
Increase (decrease) in payment of interest arising from financing activities	omse_IncreaseDecreaseInPaymentOfInterestArisingFromFinancingActivities	(253,000)
Increase (decrease) in payment of interest arising from financing activities	omse_IncreaseDecreaseInPaymentOfInterestArisingFromFinancingActivities	(162,000)
Increase (decrease) in payment of interest arising from financing activities	omse_IncreaseDecreaseInPaymentOfInterestArisingFromFinancingActivities	(5,000)
Increase (decrease) in payment of interest arising from financing activities	omse_IncreaseDecreaseInPaymentOfInterestArisingFromFinancingActivities	(24,000)
Increase (decrease) in payment of interest arising from financing activities	omse_IncreaseDecreaseInPaymentOfInterestArisingFromFinancingActivities	(191,000)
Shares Authorised	omse_SharesAuthorised	50,000
Decrease In Defined Benefit Obligation Due To DecreaseIn Actuarial Assumption Of Future Salary Growth	omse_DecreaseInDefinedBenefitObligationDueToDecreaseInActuarialAssumptionOfFutureSalaryGrowth	(76,000)
Decrease In Defined Benefit Obligation Due To DecreaseIn Actuarial Assumption Of Future Salary Growth	omse_DecreaseInDefinedBenefitObligationDueToDecreaseInActuarialAssumptionOfFutureSalaryGrowth	$ (193,000)
Dilutive Effect Of Issuable Shares On Weighted Average Number Of Ordinary Shares	omse_DilutiveEffectOfIssuableSharesOnWeightedAverageNumberOfOrdinaryShares	36,900,000
Dilutive Effect Of Issuable Shares On Weighted Average Number Of Ordinary Shares	omse_DilutiveEffectOfIssuableSharesOnWeightedAverageNumberOfOrdinaryShares	36,900,000
Current Deposits	omse_CurrentDeposits	$ 175,000
Current Deposits	omse_CurrentDeposits	1,129,000
Equipment costs	omse_EquipmentCosts	980,000
Equipment costs	omse_EquipmentCosts	732,000
Equipment costs	omse_EquipmentCosts	227,000
Equipment costs	omse_EquipmentCosts	1,002,000
Repayment from/(loan to) related parties	omse_RepaymentFromLoanToRelatedParties	(20,981,000)
Repayment from/(loan to) related parties	omse_RepaymentFromLoanToRelatedParties	$ 15,743,000
Related Party Transactions Amount Payable Settlement Period	omse_RelatedPartyTransactionsAmountPayableSettlementPeriod	30 days
Related Party Transactions Amount Payable Settlement Period	omse_RelatedPartyTransactionsAmountPayableSettlementPeriod	60 days
Lease period	omse_LeasePeriod	3 years
Lease period	omse_LeasePeriod	20 years
Lease Liabilities, Original Currency	omse_LeaseLiabilitiesOriginalCurrency	USD/MYR/SAR/THB/BND
Payments To Related Parties	omse_PaymentsToRelatedParties	$ 1,000
Payments To Related Parties	omse_PaymentsToRelatedParties	(1,585,000)
Increase In Defined Benefit Obligation Due To Increase In Actuarial Assumption Of Future Salary Growth	omse_IncreaseInDefinedBenefitObligationDueToIncreaseInActuarialAssumptionOfFutureSalaryGrowth	82,000
Increase In Defined Benefit Obligation Due To Increase In Actuarial Assumption Of Future Salary Growth	omse_IncreaseInDefinedBenefitObligationDueToIncreaseInActuarialAssumptionOfFutureSalaryGrowth	$ 239,000
Lease Liabilities, Maturity	omse_LeaseLiabilitiesMaturity	2026
Lease Liabilities, Maturity	omse_LeaseLiabilitiesMaturity	2040
Interest Bearing Liabilities	omse_InterestBearingLiabilities	$ 7,283,000
Interest Bearing Liabilities	omse_InterestBearingLiabilities	9,088,000
Premises costs	omse_PremisesCosts	1,925,000
Premises costs	omse_PremisesCosts	1,387,000
Premises costs	omse_PremisesCosts	623,000
Premises costs	omse_PremisesCosts	$ 2,005,000
Conversion Of Convertible Notes To Shares	omse_ConversionOfConvertibleNotesToShares	1,845,000
Conversion Of Convertible Notes To Shares	omse_ConversionOfConvertibleNotesToShares	0
Unrecognised deferred tax assets description	omse_UnrecognisedDeferredTaxAssetsDescription	As of March 31, 2025 and 2024, there were no net operating losses carried forward and thus no deferred tax assets are recognized, as investment holding company in Singapore cannot carry forward any unutilized losses to set-off the income of future Years of Assessment.
Number Of Shares Issued New	omse_NumberOfSharesIssuedNew	5,000
Right Of Use Assets Recognised As Of Acquisition Date	omse_RightOfUseAssetsRecognisedAsOfAcquisitionDate	$ 5,582,000
Increase Decrease Through Transferred to Trade Receivables	omse_IncreaseDecreaseThroughTransferredToTradeReceivables	(1,730,000)
Increase Decrease Through Transferred to Trade Receivables	omse_IncreaseDecreaseThroughTransferredToTradeReceivables	(225,000)
Increase Decrease Through Transferred to Trade Receivables	omse_IncreaseDecreaseThroughTransferredToTradeReceivables	(1,364,000)
Increase Decrease Through Transferred to Trade Receivables	omse_IncreaseDecreaseThroughTransferredToTradeReceivables	(672,000)
Goods and services tax payable net	omse_GoodsAndServicesTaxPayableNet	(0)
Goods and services tax payable net	omse_GoodsAndServicesTaxPayableNet	906,000
Capital advances from potential investors	omse_CapitalAdvancesFromPotentialInvestors	5,000,000
Transportation, travel and accommodation	omse_TransportationTravelAndAccommodation	164,000
Transportation, travel and accommodation	omse_TransportationTravelAndAccommodation	155,000
Transportation, travel and accommodation	omse_TransportationTravelAndAccommodation	36,000
Transportation, travel and accommodation	omse_TransportationTravelAndAccommodation	136,000
Repayment of Amount Due to Former Related Party and Loans and Borrowings	omse_RepaymentOfAmountDueToFormerRelatedPartyAndLoansAndBorrowings	6,504,000
Repayment of Amount Due to Former Related Party and Loans and Borrowings	omse_RepaymentOfAmountDueToFormerRelatedPartyAndLoansAndBorrowings	3,874,000
Repayment of Amount Due to Former Related Party and Loans and Borrowings	omse_RepaymentOfAmountDueToFormerRelatedPartyAndLoansAndBorrowings	500,000
Other Assets Recognised As Of Acquisition Date	omse_OtherAssetsRecognisedAsOfAcquisitionDate	$ 5,006,000
Conversion of Convertible Notes Shares	omse_ConversionOfConvertibleNotesShares	1,845,000
Proceeds From Loans From Related Parties	omse_ProceedsFromLoansFromRelatedParties	$ 8,845,000
Proceeds due to a related party	omse_ProceedsDueToARelatedParty	8,845,000
Proceeds due to a related party	omse_ProceedsDueToARelatedParty	0
Proceeds due to a related party	omse_ProceedsDueToARelatedParty	0
Proceeds due to a related party	omse_ProceedsDueToARelatedParty	8,845,000
Allotment of Ordinary Shares	omse_AllotmentOfOrdinaryShares	5,000,000
Loans And Borrowings Arising From Financing Activities Beginning Balance	omse_LoansAndBorrowingsArisingFromFinancingActivitiesBeginningBalance	0
Amount Due To Related Parties Recognized As OF Acquisition Date	omse_AmountDueToRelatedPartiesRecognizedAsOFAcquisitionDate	8,845,000
Interest Charged Outstanding Balances	omse_InterestChargedOutstandingBalances	0
Non current prepayments and other non current assets	omse_NonCurrentPrepaymentsAndOtherNonCurrentAssets	1,327,000
Non current prepayments and other non current assets	omse_NonCurrentPrepaymentsAndOtherNonCurrentAssets	694,000
Related Party Transaction Cash Consideration	omse_RelatedPartyTransactionCashConsideration	12,800,000
Related Party Transaction Cash Consideration	omse_RelatedPartyTransactionCashConsideration	$ 11,600,000
Number Of Ordinary Shares Converted From Bond	omse_NumberOfOrdinarySharesConvertedFromBond	750
Number Of Ordinary Shares Converted From Bond	omse_NumberOfOrdinarySharesConvertedFromBond	750
Tax Provision Recognised As Of Acquisition Date	omse_TaxProvisionRecognisedAsOfAcquisitionDate	$ 6,267,000
Aditional payment on equity method investments recognized as capital injection	omse_AditionalPaymentOnEquityMethodInvestmentsRecognizedAsCapitalInjection	800,000
Purchase Consideration Paid Received	omse_PurchaseConsiderationPaidReceived	2,000,000
Other Liabilities Recognised As Of Acquisition Date	omse_OtherLiabilitiesRecognisedAsOfAcquisitionDate	11,743,000
Conversion Of Convertible Bond To Shares	omse_ConversionOfConvertibleBondToShares	5,000,000
CAYMAN ISLANDS
Impact of different tax rate in other jurisdiction amount	omse_ImpactOfDifferentTaxRateInOtherJurisdictionAmount	$ 0

Financial Instruments - Summary of Foreign Currency Exposure (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Mar. 31, 2024
Foreign Currency Exposure [Line Items]
Net exposure	$ 6,361	$ 7,447

Material Accounting Policies - Additional Information (Details) - 12 months ended Mar. 31, 2025 ฿ in Millions, Rp in Billions	USD ($) Segment	BND ($)	IDR (Rp)	SGD ($)	THB (฿)	MYR (RM)
Material accounting policies details [Line Items]
Closing foreign exchange rate calculated using reporting currency \| $	$ 1
Cash deposit insured		$ 50,000	Rp 2	$ 100,000	฿ 1	RM 250,000
Number of reportable segments \| Segment	6

Finance Income & Costs - Summary of Finance Income and Costs (Details) - USD ($) $ in Thousands	3 Months Ended	10 Months Ended	12 Months Ended
	Jun. 15, 2023	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2023
Finance income
Interest income from amount due from related parties	$ 65	$ 0	$ 0	$ 204
Finance costs
Interest expenses from amount due to related parties	162	0	0	1,759
Interest expenses from employees' defined benefits obligation	$ 9	$ 33	$ 31	$ 37

Organization And Principal Activities - Additional Information (Details) - USD ($) $ in Millions		6 Months Ended
	Jan. 04, 2023	Jul. 15, 2023
Organization and principal activities [line items]
Business acquisition consideration paid	$ 2.0
Legacy cash pooling arrangement principal balance		$ 8.8

Inventories - Schedule of Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Mar. 31, 2024
Disclosure of inventory [abstract]
Less: Allowance for inventories obsolescence	$ (2,515)	$ (1,944)

Organization and Principal Activities - Summary of Detailed Information About Details of Subsidiaries (Details)	12 Months Ended
	Mar. 31, 2025
Organization and principal activities [line items]
Date of incorporation	Jan. 25, 2005

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Mar. 31, 2025
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Financial Instruments - Summary of Categories of Financial Instruments (Parenthetical) (Details) $ in Millions	Mar. 31, 2024 USD ($)
Categories of financial assets and liabilities [Line items]
Accrued interest	$ 0.7

Income Tax Expenses - Summary of Movement In Deferred Tax Balance (Details) $ in Thousands	12 Months Ended
	Mar. 31, 2023 USD ($)
Movement in deferred tax balance [line items]
Deferred tax asset allowances	$ (1,031)