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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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Asset Impairments - Additional Information (Detail) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2017 USD ($) Vessel	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($) Vessel	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2017 USD ($) Vessel	Mar. 31, 2016 USD ($) Vessel	Mar. 31, 2015 USD ($) Vessel
Derivatives, Fair Value [Line Items]
Asset impairment	$ 64,857	$ 253,422	$ 129,562	$ 36,886	$ 55,540	$ 15,141	$ 31,672	$ 14,958	$ 484,727	$ 117,311	$ 14,525
Number of vessels impaired during the period \| Vessel									132	58	12
Fair value of assets incurring impairment									$ 933,068	$ 422,655	$ 28,509
Net book value of assets	$ 2,864,762				$ 3,551,291				$ 2,864,762	$ 3,551,291
Number of vessels operating \| Vessel	244				253				244	253
Total carrying value of vessels	$ 3,407,760				$ 4,666,749				$ 3,407,760	$ 4,666,749
Stacked Vessels and Other Assets
Derivatives, Fair Value [Line Items]
Asset impairment									$ 265,200
Number of vessels impaired during the period \| Vessel									75
Fair value of assets incurring impairment									$ 545,900
Number of vessels stacked \| Vessel	27								27
Net book value of assets	$ 246,000								$ 246,000
Active Vessels
Derivatives, Fair Value [Line Items]
Asset impairment									$ 178,500
Number of vessels impaired during the period \| Vessel									57
Fair value of assets incurring impairment									$ 362,100
Net book value of assets	$ 1,600,000								$ 1,600,000
Number of vessels active \| Vessel	86								86
Stacked and Active Vessels
Derivatives, Fair Value [Line Items]
Number of vessels operating \| Vessel	244								244
Total carrying value of vessels	$ 2,800,000								$ 2,800,000