Recently Adopted Accounting Pronouncements - Additional Information (Detail) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($)
Accounting Changes And Error Corrections [Abstract]
Reduction in trade and other receivables,net	$ 0.2

Increase (decrease) in trade and other receivables net.

No definition available.

Name:	tdw_IncreaseDecreaseInTradeAndOtherReceivablesNet
Namespace Prefix:	tdw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration