XML 157 R137.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Commitment and Contingencies (Repairs to U.S. Flagged Vessels Operating Abroad) - Additional Information (Detail) | 9 Months Ended
--- | ---
Dec. 31, 2017
Commitments And Contingencies Disclosure [Abstract] |
Percentage of vessel repair duty | 50.00%

X
- Definition Percentage of custom duty for vessel repair. + References No definition available. + Details
Name: | tdw_PercentageOfCustomDutyForVesselRepair
Namespace Prefix: | tdw_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_CommitmentsAndContingenciesDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration