Segment Reporting - Information about Operations in Different Segments (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Segment Reporting Information [Line Items]
Revenues	[1]	$ 788,673	$ 706,627	$ 1,308,104	$ 1,435,659
Operating income (loss)		87,199	56,988	143,184	92,981
Interest expense, net		(21,204)	(12,655)	(38,910)	(23,893)
Other non-operating income (expense), net		(2,491)	(2,851)	(1,877)	(6,242)
Income before provision for income taxes		63,504	41,482	102,397	62,846
Capital expenditures		18,073	138,774	80,922	170,674
Depreciation and amortization		28,304	24,387	49,685	48,929
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income (loss)		139,072	103,203	233,407	210,997
Operating Segments [Member] | AEA [Member]
Segment Reporting Information [Line Items]
Revenues	[1]	41,564	86,810	69,695	149,435
Operating income (loss)		(11,302)	13,861	(11,119)	29,960
Capital expenditures		10,074	941	15,325	3,526
Depreciation and amortization		7,395	9,406	11,408	19,725
Operating Segments [Member] | MEA [Member]
Segment Reporting Information [Line Items]
Revenues	[1]	556,612	317,834	866,664	588,089
Operating income (loss)		117,480	53,297	181,857	99,336
Capital expenditures		4,779	2,469	10,631	4,703
Depreciation and amortization		13,762	6,562	21,665	11,908
Operating Segments [Member] | ASA [Member]
Segment Reporting Information [Line Items]
Revenues	[1]	190,497	301,983	371,745	698,135
Operating income (loss)		32,894	36,045	62,669	81,701
Capital expenditures		2,224	134,567	5,736	161,575
Depreciation and amortization		5,372	6,289	12,947	12,907
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Operating income (loss)	[2]	(51,873)	(46,215)	(90,223)	(118,016)
Capital expenditures	[3]	996	797	49,230	870
Depreciation and amortization		$ 1,775	$ 2,130	$ 3,665	$ 4,389

[1] Intersegment transactions included in revenues were not significant for either of the periods presented.

[2] Corporate and Other operating results for the first half of 2017 and 2016 include a $3 million gain on sale of assets and $32 million impairment charge related to our Agile vessel, respectively.

[3] Corporate and Other capital expenditures in the first half of 2017 include the purchase of the Amazon, a pipelay and construction vessel. Following the purchase we sold this vessel to an unrelated third party and simultaneously entered into an 11-year bareboat charter agreement, see Note 8, Sale Leaseback.