CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		4 Months Ended	5 Months Ended	12 Months Ended
		Jul. 31, 2017	Dec. 31, 2017	Dec. 31, 2018	Mar. 31, 2017
Operating activities:
Net loss			$ (38,726)	$ (171,771)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization			20,131	51,332
Amortization of deferred drydocking and survey costs			206	6,961
Amortization of debt premiums and discounts			(715)	(1,856)
Provision for deferred income taxes				572
Gain on asset dispositions, net			(6,616)	(10,624)
Impairment of due from affiliate				20,083
Long-lived asset impairments	[1]		16,777	61,132
Loss on debt extinguishment				8,119
Changes in investments in, at equity, and advances to unconsolidated companies			(4,531)	28,177
Compensation expense – stock based			3,731	13,406
Changes in operating assets and liabilities, net:
Trade and other receivables			2,312	9,088
Changes in due to/from affiliate, net			(2,373)	28,644
Marine operating supplies			1,229	(1,955)
Other current assets			10,305	10,893
Accounts payable			(1,259)	(15,174)
Accrued expenses			(24,896)	(13,489)
Accrued property and liability losses			(176)	141
Other current liabilities			(4,026)	1,332
Other liabilities and deferred credits			(1,089)	(2,023)
Deferred drydocking and survey costs			(3,414)	(25,968)
Other, net			(2,416)	6,921
Net cash provided by (used in) operating activities			(35,546)	3,941
Cash flows from investing activities:
Proceeds from sales of assets			32,742	46,115
Additions to properties and equipment			(9,834)	(21,391)
Cash and cash equivalents from stock based merger				43,806
Net cash provided by investing activities			22,908	68,530
Cash flows from financing activities:
Principal payments on long-term debt			(1,176)	(105,169)
Cash payments to General Unsecured Creditors			(93,719)	(8,377)
Loss on debt extinguishment				(8,119)
Cash received for issuance of common stock			2	3
Tax on share-based award				(4,400)
Other				(2,000)
Net cash used in financing activities			(94,893)	(128,062)
Net change in cash, cash equivalents and restricted cash			(107,531)	(55,591)
Cash, cash equivalents and restricted cash at beginning of period			560,866	453,335
Cash, cash equivalents and restricted cash at end of period		$ 560,866	453,335	397,744
Cash paid during the year for:
Interest, net of amounts capitalized			8,223	32,326
Income taxes			4,654	16,828
Supplemental disclosure of noncash investing activities:
Merger with GulfMark				285,492
Supplemental disclosure of noncash financing activities:
Common stock issued for GulfMark merger				$ 285,492
Predecessor
Operating activities:
Net loss		(1,646,909)			$ (650,011)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Reorganization items (non-cash)		1,368,882
Depreciation and amortization		47,447			167,291
Provision for deferred income taxes		(5,543)			(2,200)
Gain on asset dispositions, net		(3,561)			(24,099)
Long-lived asset impairments	[1]	184,748			484,727
Changes in investments in, at equity, and advances to unconsolidated companies		(4,252)			(7,613)
Compensation expense – stock based		1,707			3,278
Excess tax liability on stock options exercised					4,927
Changes in operating assets and liabilities, net:
Trade and other receivables		6,286			104,829
Changes in due to/from affiliate, net		1,301			20,829
Marine operating supplies		88			2,285
Other current assets		(1,840)			(12,523)
Accounts payable		8,157			(17,531)
Accrued expenses		17,245			(18,687)
Accrued property and liability losses		(822)			262
Other current liabilities		(2,337)			(26,658)
Other liabilities and deferred credits		2,884			(2,657)
Other, net		4,932			3,372
Net cash provided by (used in) operating activities		(21,587)			29,821
Cash flows from investing activities:
Proceeds from sales of assets		2,172			14,797
Additions to properties and equipment		(2,265)			(25,499)
Payments related to novated construction contract		5,272
Refunds from cancelled vessel construction contracts					25,565
Net cash provided by investing activities		5,179			14,863
Cash flows from financing activities:
Principal payments on long-term debt		(5,124)			(10,069)
Cash payments to General Unsecured Creditors		(122,806)
Other		(1,200)			(6,649)
Net cash used in financing activities		(129,130)			(16,718)
Net change in cash, cash equivalents and restricted cash		(145,538)			27,966
Cash, cash equivalents and restricted cash at beginning of period		706,404	$ 560,866		678,438
Cash, cash equivalents and restricted cash at end of period		560,866			706,404
Cash paid during the year for:
Interest, net of amounts capitalized		1,577			70,687
Income taxes		$ 4,740			26,916
Supplemental disclosure of noncash investing activities:
Additions to properties and equipment					$ 5,047

[1] The twelve months ended December 31, 2018, the period August 1, 2017 through December 31, 2017 and the twelve months ended March 31, 2017 included $3.5 million, $2.3 million and $2.2 million respectively, of impairments related to inventory and other non-vessel assets. There were no impairments to non-vessel assets during the period April 1, 2017 through July 31, 2017.