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Investment in Unconsolidated Companies - Additional Information (Detail) $ in Thousands	1 Months Ended	3 Months Ended								4 Months Ended		5 Months Ended		12 Months Ended
	Jul. 31, 2017 USD ($) Vessel	Dec. 31, 2019 USD ($) Vessel	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($) Vessel	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) Vessel	Jun. 30, 2017 USD ($)	Jul. 31, 2017 USD ($) Vessel	Jul. 31, 2017 USD ($) Vessel	Dec. 31, 2017 USD ($) Vessel	Dec. 31, 2017 USD ($) Vessel	Dec. 31, 2019 USD ($) Vessel	Dec. 31, 2018 USD ($) Vessel	Mar. 31, 2017 USD ($)
Schedule of Equity Method Investments [Line Items]
Due from affiliate		$ 125,972		$ 132,951										$ 125,972	$ 132,951
Impairments Charges	$ 21,325	32,549	$ 5,224	36,878	$ 16,853	$ 1,215	$ 6,186	$ 16,777	$ 163,423		$ 184,748		$ 16,777	37,773	61,132
Due to affiliate		$ 50,186		34,972										50,186	34,972
Total revenues											151,369		178,753	$ 486,549	406,520
Sonatide Marine, Ltd.
Schedule of Equity Method Investments [Line Items]
Ownership percentage in unconsolidated affiliates		49.00%												49.00%
Due from affiliate	252,393	$ 89,246		109,176				230,315		$ 252,393	252,393	$ 230,315	230,315	$ 89,246	109,176	$ 262,652
Cash		49,200												49,200
Working capital to satisfy net due from affiliate		58,000												58,000
Impairments Charges															20,000
Due to affiliate	$ 123,899	$ 31,475		$ 29,347				$ 99,448		$ 123,899	$ 123,899	$ 99,448	$ 99,448	$ 31,475	$ 29,347	$ 132,857
Number of vessels operating \| Vessel		4												4
Number of vessels stacked \| Vessel														2
Sonatide Marine, Ltd. \| ANGOLA
Schedule of Equity Method Investments [Line Items]
Number of vessels operating \| Vessel	50	32		37				43		50	50	43	43	32	37
Number of vessels stacked \| Vessel										21		16		13	16
Total revenues										$ 34,000		$ 34,000		$ 52,100	$ 59,000
Percentage of Angolan operation revenue										23.00%		20.00%		10.90%	15.00%
Sonatide Marine, Ltd. \| Trade Accounts Receivable
Schedule of Equity Method Investments [Line Items]
Net trade accounts receivable		$ 8,800												$ 8,800
Sonatide Marine, Ltd. \| Angola, Kwanza
Schedule of Equity Method Investments [Line Items]
Cash		$ 8,900												$ 8,900
Maximum \| Sonatide Marine Ltd and DTDW Holdings Ltd.
Schedule of Equity Method Investments [Line Items]
Ownership percentage in unconsolidated affiliates		50.00%												50.00%