XML 153 R141.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Commitments and Contingencies (Sonatide Joint Venture) - Additional Information (Detail) $ in Thousands | 1 Months Ended | 3 Months Ended | 4 Months Ended | 5 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Jul. 31, 2017 USD ($) | Jun. 30, 2018 USD ($) Vessel | Jul. 31, 2017 USD ($) | Dec. 31, 2017 USD ($) Vessel | Jun. 30, 2018 USD ($) Vessel | Jun. 30, 2017 USD ($) Vessel | Mar. 31, 2017 USD ($) | Jun. 30, 2014 Vessel
Commitments And Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Due from affiliate |  |  | $ 197,059 |  |  | $ 230,315 | $ 197,059 |  |  |  |
Due to affiliate |  |  | 62,353 |  |  | 99,448 | 62,353 |  |  |  |
Commissions payable |  |  | 2,488 | [1] |  | 1,898 | 2,488 | [1] |  |  |
Total revenues |  |  | 105,601 |  |  | 178,753 | 197,094 |  |  |  |
Investments in, at equity, and advances to unconsolidated companies |  |  | 1,335 |  |  | 29,216 | 1,335 |  |  |  |
Cash and cash equivalents |  |  | 459,286 |  |  | $ 432,035 | 459,286 |  |  |  |
Number of vessels operating | Vessel | [2] |  |  |  |  | 227 |  |  |  |  |
Dividend received in excess of investment |  |  |  |  |  |  | 4,900 |  |  |  |
Vessel Revenues |  |  |  |  |  |  |  |  |  |  |
Commitments And Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  | $ 104,174 |  |  | $ 171,884 | $ 191,668 |  |  |  |
ANGOLA |  |  |  |  |  |  |  |  |  |  |
Commitments And Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of vessels operating | Vessel |  |  | 37 |  |  |  | 37 |  |  |  | 84
Decrease in number of vessels operating | Vessel |  |  | 47 |  |  |  | 47 |  |  |  |
Number of active vessels | Vessel |  |  | 22 |  |  |  | 22 |  |  |  | 80
Decrease in number of active vessels | Vessel |  |  | 58 |  |  |  | 58 |  |  |  |
Devaluation Of Angolan kwanza Versus US Dollar |  |  |  |  |  |  |  |  |  |  |
Commitments And Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Foreign currency exchange rate |  |  | 250 |  |  | 168 | 250 |  |  |  |
Percentage of devaluation of currency |  |  |  |  |  |  | 49.00% |  |  |  |
Percentage of foreign exchange loss recognized |  |  |  |  |  |  | 49.00% |  |  |  |
Estimated exchange loss |  |  |  |  |  |  | $ 20,600 |  |  |  |
Sonatide joint venture |  |  |  |  |  |  |  |  |  |  |
Commitments And Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Due from affiliate |  |  | $ 153,000 |  |  | $ 230,000 | 153,000 |  |  | $ 263,000 |
Unpaid vessel revenue |  |  | 25,000 |  |  | 44,000 | 25,000 |  |  |  |
Due to affiliate |  |  | 47,000 |  |  | 99,000 | 47,000 |  |  | 133,000 |
Commissions payable |  |  | $ 30,200 |  |  | 36,400 | 30,200 |  |  |  |
Due from affiliate and due to affiliate |  |  |  |  |  | $ 33,000 | $ 55,000 |  |  |  |
Ownership Interest In Joint Venture |  |  | 49.00% |  |  | 49.00% | 49.00% |  |  |  |
Investments in, at equity, and advances to unconsolidated companies |  |  | $ 0 |  |  | $ 27,000 | $ 0 |  |  | 45,000 |
Investment balance in difference between carrying value and net assets of the joint venture |  | $ 28,000 |  |  | $ 28,000 |  |  |  |  |  |
Amortization period of basis difference equity method investments |  | 10 years |  |  |  |  |  |  |  |  |
Dividend received |  |  |  |  |  |  | 12,300 |  |  |  |
Sonatide joint venture | U.S. dollars initially received by Sonatide on behalf of the company or dollars collected from other customers |  |  |  |  |  |  |  |  |  |  |
Commitments And Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Proceeds from related party |  |  |  |  | 19,000 | 20,000 | 47,000 |  |  |  |
Sonatide joint venture | Sonatide's converting kwanzas into dollars and subsequent payment to company |  |  |  |  |  |  |  |  |  |  |
Commitments And Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Proceeds from related party |  |  |  |  | 3,000 | 1,000 | 4,000 |  |  |  |
Sonatide joint venture | ANGOLA |  |  |  |  |  |  |  |  |  |  |
Commitments And Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Proceeds from related party |  |  |  |  | 22,000 | 21,000 | $ 51,000 |  |  |  |
Total revenues |  |  |  |  | $ 34,000 | $ 34,000 |  |  |  | $ 127,000 |
Percentage of Angolan operation revenue |  |  |  |  | 23.00% | 20.00% | 15.00% |  | 20.00% | 22.00% |
"Number of vessels transferred out of Angola | Vessel" |  |  |  |  | 3 | 3 | 8 |  |  | 22 |
Number of vessels operating | Vessel |  |  | 38 |  |  |  | 38 |  | 53 |  |
Number of vessels stacked | Vessel |  |  | 17 |  |  |  | 17 |  | 23 |  |
Sonatide joint venture | ANGOLA | Vessel Revenues |  |  |  |  |  |  |  |  |  |  |
Commitments And Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  | $ 29,000 |  | $ 53,000 |  |
Sonatide joint venture | Angolan kwanza-denominated |  |  |  |  |  |  |  |  |  |  |
Commitments And Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Bank deposits maintained |  |  | $ 67,000 |  |  | $ 81,000 | 67,000 |  |  |  |
Cash and cash equivalents |  |  | $ 43,000 |  |  |  | $ 43,000 |  |  |  |
[1] | Excludes $30.2 million and $36.4 million of commissions due to Sonatide at June 30, 2018 and December 31, 2017, respectively. These amounts are included in amounts due to affiliates.
[2] | Vessel count excludes vessels operated under sale leaseback agreements.

X
- Definition Amortization period of basis difference equity method investments. + References No definition available. + Details
Name: | tdw_AmortizationPeriodOfBasisDifferenceEquityMethodInvestments
Namespace Prefix: | tdw_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Commitments and Contingencies Disclosure [Line Items] + References No definition available. + Details
Name: | tdw_CommitmentsAndContingenciesDisclosureLineItems
Namespace Prefix: | tdw_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Decrease In Number Of Active Vessel + References No definition available. + Details
Name: | tdw_DecreaseInNumberOfActiveVessel
Namespace Prefix: | tdw_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Decrease In Number Of Vessel + References No definition available. + Details
Name: | tdw_DecreaseInNumberOfVessel
Namespace Prefix: | tdw_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Dividend received in excess of investment. + References No definition available. + Details
Name: | tdw_DividendReceivedInExcessOfInvestment
Namespace Prefix: | tdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Due from affiliate balance invoiced but unpaid. + References No definition available. + Details
Name: | tdw_DueFromAffiliateBalanceInvoicedButUnpaid
Namespace Prefix: | tdw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number Of Active Vessel + References No definition available. + Details
Name: | tdw_NumberOfActiveVessel
Namespace Prefix: | tdw_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of vessels. + References No definition available. + Details
Name: | tdw_NumberOfVessel
Namespace Prefix: | tdw_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of vessels stacked. + References No definition available. + Details
Name: | tdw_NumberOfVesselsStacked
Namespace Prefix: | tdw_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number Of Vessels Transferred + References No definition available. + Details
Name: | tdw_NumberOfVesselsTransferred
Namespace Prefix: | tdw_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of currency devaluation. + References No definition available. + Details
Name: | tdw_PercentageOfCurrencyDevaluation
Namespace Prefix: | tdw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of foreign exchange loss recognized. + References No definition available. + Details
Name: | tdw_PercentageOfForeignExchangeLossRecognized
Namespace Prefix: | tdw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Sales revenue, services, percentage. + References No definition available. + Details
Name: | tdw_SalesRevenueServicesPercentage
Namespace Prefix: | tdw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Carrying value as of the balance sheet date of obligations incurred through that date and payable for sales commissions. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6911-107765 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6935-107765 + Details
Name: | us-gaap_AccruedSalesCommissionCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3044-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6676-107765 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_CashAndCashEquivalentsAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership, due within 1 year (or 1 business cycle). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39599-107864 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(k)(1)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 852 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6918054&loc=d3e56071-112765 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 + Details
Name: | us-gaap_DueFromAffiliateCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition A bank's noninterest bearing demand deposits in other banks (such as correspondents). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.1) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_DueFromBanks
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)(a)(5)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(k)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(12)(b)(3)) -URI http://asc.fasb.org/extlink&oid=6488278&loc=d3e603758-122996 + Details
Name: | us-gaap_DueToAffiliateCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
Name: | us-gaap_EquityMethodInvestmentDifferenceBetweenCarryingAmountAndUnderlyingEquity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
Name: | us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 25 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8813-108599 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_EquityMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The reporting currency-denominated expense (including losses) amount. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6897108&loc=SL6897125-166521 + Details
Name: | us-gaap_ExpensesAndLossesReportingCurrencyDenominatedValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6897108&loc=SL6897125-166521 + Details
Name: | us-gaap_ForeignCurrencyExchangeRateTranslation1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | instant

X
- Definition The increase (decrease) during the reporting period in receivables to be collected from other entities that could exert significant influence over the reporting entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
Name: | us-gaap_IncreaseDecreaseInDueFromRelatedParties
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash inflow from an entity that is affiliated with the entity by means of direct or indirect ownership. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromContributionsFromAffiliates
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Dividends received on equity and other investments during the current period. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 16 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3337-108585 + Details
Name: | us-gaap_ProceedsFromDividendsReceived
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045 + Details
Name: | us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | srt_ProductOrServiceAxis=us-gaap_ServiceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=country_AO
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IntercompanyForeignCurrencyBalanceByDescriptionAxis=tdw_DevaluationOfAngolanKwanzaVersusUSDollarMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=tdw_SonatideMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=tdw_ScenarioOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=tdw_ScenarioTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CashAndCashEquivalentsAxis=tdw_BankDepositMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |