The percentage of equity interests for collateral of the debt instrument.

No definition available.

Name:	tdw_DebtInstrumentCollateralPercentageOfEquityInterests
Namespace Prefix:	tdw_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the prepayment premiums percentage.

+ References

No definition available.

+ Details

Name:	tdw_DebtInstrumentCovenantPrepaymentPremiumPercentage
Namespace Prefix:	tdw_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Relates to adjustment to the prepayment premium percentage.

+ References

No definition available.

+ Details

Name:	tdw_DebtInstrumentCovenantPrepaymentPremiumPercentageIncreaseDecrease
Namespace Prefix:	tdw_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Minimum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility, as a percent of interest-bearing debt.

+ References

No definition available.

+ Details

Name:	tdw_LineOfCreditFacilityMinimumBorrowingCapacityPercentOfInterestbearingDebt
Namespace Prefix:	tdw_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Minimum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

No definition available.

+ Details

Name:	tdw_LineOfCreditFacilityMinimumBorrowingCommitment
Namespace Prefix:	tdw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Ratio of Fair Market Value of Collateral to Outstanding Debt

+ References

No definition available.

+ Details

Name:	tdw_RatioOfFairMarketValueOfCollateralToOutstandingDebt
Namespace Prefix:	tdw_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio of Interest-bearing Debt to EBITDA

+ References

No definition available.

+ Details

Name:	tdw_RatioOfInterestbearingDebtToEbitda
Namespace Prefix:	tdw_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482949/835-30-55-8

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69C

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

+ Details

Name:	us-gaap_DebtInstrumentRedemptionPricePercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates type of variable interest rate on debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

+ Details

Name:	us-gaap_DebtInstrumentVariableInterestRateTypeExtensibleEnumeration
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481303/470-50-40-2

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481303/470-50-40-4

+ Details

Name:	us-gaap_GainsLossesOnExtinguishmentOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-SubTopic 10
-Topic 825
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482881/825-10-55-10

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-10

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482881/825-10-55-12

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

+ Details

Name:	us-gaap_LongTermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

+ References

No definition available.

+ Details

Name:	us-gaap_RedemptionPremium
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(8))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

+ Details

Name:	us-gaap_WriteOffOfDeferredDebtIssuanceCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=tdw_DnbBankAsaNewYorkMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_FederalFundsEffectiveSwapRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_SecuredOvernightFinancingRateSofrMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=tdw_MarginRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=tdw_ApplicableMarginRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=tdw_The2023NotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentRedemptionPeriodAxis=us-gaap_DebtInstrumentRedemptionPeriodTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=tdw_VesselFacilityAgreementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TypeOfArrangementAxis=tdw_DeliveryOfVesselsPerArrangementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=tdw_NordicBondMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=tdw_GOLPAndTMIIMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=tdw_NordicBond1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=tdw_TrancheATermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=tdw_TrancheBTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=tdw_NordicBondMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=tdw_ExtinguishedDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 8 - Debt (Details Textual) $ in Thousands, € in Millions			3 Months Ended		9 Months Ended
	Jul. 07, 2025 USD ($)	Jul. 05, 2023 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2025 EUR (€)	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)	Jul. 03, 2023 USD ($)	Nov. 16, 2021 USD ($)
Gain (Loss) on Extinguishment of Debt			$ (27,101)	$ 0	$ (27,101)	$ 0
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	Secured Overnight Financing Rate (SOFR) [Member]
Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity								$ 25,000
Revolving Credit Facility [Member] \| DNB Bank ASA, New York [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 250,000
Line of Credit Facility, Minimum Borrowing Commitment	$ 20,000
Line of Credit Facility, Minimum Borrowing Capacity, Percent of Interest-bearing Debt	10.00%
Ratio of Interest-bearing Debt to EBITDA	3
Ratio of Fair Market Value of Collateral to Outstanding Debt	2.5
Revolving Credit Facility [Member] \| DNB Bank ASA, New York [Member] \| Fed Funds Effective Rate Overnight Index Swap Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	0.50%
Revolving Credit Facility [Member] \| DNB Bank ASA, New York [Member] \| Secured Overnight Financing Rate (SOFR) [Member]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Revolving Credit Facility [Member] \| DNB Bank ASA, New York [Member] \| Margin Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	1.00%
Revolving Credit Facility [Member] \| DNB Bank ASA, New York [Member] \| Minimum [Member] \| Applicable Margin Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	2.50%
Revolving Credit Facility [Member] \| DNB Bank ASA, New York [Member] \| Maximum [Member] \| Applicable Margin Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	3.50%
The 2023 Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage	9.125%
Debt Instrument, Face Amount	$ 650,000
The 2023 Notes [Member] \| Debt Instrument, Redemption, Period One [Member]
Debt Instrument, Redemption Price, Percentage	100.00%
The 2023 Notes [Member] \| Debt Instrument, Redemption, Period Two [Member]
Debt Instrument, Redemption Price, Percentage	104.563%
Vessel Facility Agreements [Member] \| Delivery of Vessels Per Arrangement [Member]
Debt Instrument, Face Amount			$ 26,700		$ 26,700		€ 24.9
Vessel Facility Agreements [Member] \| Minimum [Member] \| Delivery of Vessels Per Arrangement [Member]
Debt Instrument, Interest Rate, Stated Percentage			2.70%		2.70%		2.70%
Vessel Facility Agreements [Member] \| Maximum [Member] \| Delivery of Vessels Per Arrangement [Member]
Debt Instrument, Interest Rate, Stated Percentage			6.30%		6.30%		6.30%
Nordic Bond [Member]
Debt Instrument, Interest Rate, Stated Percentage											8.50%
Debt Instrument, Covenant, Prepayment Premium Percentage											2.55%
Debt Instrument, Covenant, Prepayment Premium Percentage, Increase (Decrease)											0.85%
Nordic Bond [Member] \| GOLP and TMII [Member]
Debt Instrument, Collateral, Percentage of Equity Interests											66.00%
Nordic Bond 1 [Member]
Debt Instrument, Interest Rate, Stated Percentage			9.125%		9.125%		9.125%
Long-Term Debt, Fair Value			$ 697,100		$ 697,100
Secured Debt [Member]
Debt Instrument, Interest Rate, Stated Percentage											8.50%
Long-Term Debt, Fair Value									$ 218,200
Redemption Premium	$ 4,500
Debt Instrument, Face Amount		$ 325,000									$ 175,000
Secured Debt [Member] \| Tranche A Term Loan [Member]
Debt Instrument, Basis Spread on Variable Rate		5.00%
Secured Debt [Member] \| Tranche A Term Loan [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate		8.00%
Secured Debt [Member] \| Tranche B Term Loan [Member]
Debt Instrument, Basis Spread on Variable Rate		3.75%
Unsecured Debt [Member]
Debt Instrument, Interest Rate, Stated Percentage	10.375%		10.375%		10.375%		10.375%		10.375%	10.375%
Long-Term Debt, Fair Value									$ 266,100
Redemption Premium	$ 15,000
Debt Instrument, Face Amount										$ 250,000
Debt Instrument, Covenant, Prepayment Premium Percentage										6.00%
Nordic Bond [Member]
Debt Instrument, Interest Rate, Stated Percentage	8.50%		8.50%		8.50%		8.50%		8.50%
Long-Term Debt, Fair Value									$ 180,800
Extinguished Debt [Member]
Deferred Debt Issuance Cost, Writeoff			$ 7,500
Gain (Loss) on Extinguishment of Debt			$ (27,100)		$ (27,100)