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Asset Impairments, Asset Held for Sale and Other - Additional Information (Detail)	1 Months Ended	3 Months Ended								4 Months Ended	5 Months Ended	12 Months Ended
	Jul. 31, 2017 USD ($)	Dec. 31, 2019 USD ($) Vessel	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jul. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($) Vessel	Dec. 31, 2018 USD ($)
Long Term Purchase Commitment [Line Items]
Long-lived asset impairments and other	$ 21,325,000	$ 32,549,000	$ 5,224,000	$ 36,878,000	$ 16,853,000	$ 1,215,000	$ 6,186,000	$ 16,777,000	$ 163,423,000	$ 184,748,000	$ 16,777,000	$ 37,773,000	$ 61,132,000
Other assets			$ 1,800,000
Impairment charge on under construction vessel		5,800,000
Unpaid milestone payment		4,000,000.0
Stacked and Active Vessels
Long Term Purchase Commitment [Line Items]
Long-lived asset impairments and other		$ 26,700
Number of vessels stacked \| Vessel		61
Number of vessels sold \| Vessel		42
Number of vessels designated for sale \| Vessel		4										4
Remaining net book value of assets held for sale		$ 39,300,000										$ 39,300,000