Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Revenues:
Revenue	$ 647,684	$ 371,033	$ 397,038
Costs and expenses:
Vessel operating costs	397,301	261,814	268,780
Costs of other operating revenues	2,130	2,231	3,405
General and administrative	101,921	68,516	73,447
Depreciation and amortization	119,160	114,544	116,709
(Gain) loss on asset dispositions, net	(250)	2,901	(7,591)
Affiliate credit loss impairment expense	0	400	52,981
Affiliate guarantee obligation	0	0	2,000
Long-lived asset impairments and other	714	15,643	74,109
Total costs and expenses	620,976	466,049	583,840
Operating income (loss)	26,708	(95,016)	(186,802)
Other income (expense):
Foreign exchange loss	(2,827)	(369)	(5,245)
Equity in net earnings (losses) of unconsolidated companies	(221)	(3,322)	164
Dividend income from unconsolidated company	0	0	17,150
Interest income and other, net	5,397	1,605	1,228
Loss on warrants	(14,175)	0	0
Loss on early extinguishment of debt	0	(11,100)	0
Interest and other debt costs, net	(17,189)	(15,583)	(24,156)
Total other expense	(29,015)	(28,769)	(10,859)
Loss before income taxes	(2,307)	(123,785)	(197,661)
Income tax (benefit) expense	19,886	5,875	(965)
Net loss	(22,193)	(129,660)	(196,696)
Less: Net losses attributable to noncontrolling interests	(444)	(691)	(454)
Net loss attributable to Tidewater Inc.	$ (21,749)	$ (128,969)	$ (196,242)
Basic loss per common share (in dollars per share)	$ (0.49)	$ (3.14)	$ (4.86)
Diluted loss per common share (in dollars per share)	$ (0.49)	$ (3.14)	$ (4.86)
Weighted average common shares outstanding (in shares)	44,132	41,009	40,355
Dilutive effect of warrants, restricted stock units and stock options (in shares)	0	0	0
Adjusted weighted average common shares (in shares)	44,132	41,009	40,355
Vessel [Member]
Revenues:
Revenue	$ 641,404	$ 361,569	$ 386,174
Product and Service, Other [Member]
Revenues:
Revenue	$ 6,280	$ 9,464	$ 10,864