CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 36,459	$ 21,805	$ 60,654	$ 19,361
Other comprehensive income (loss), net of tax:
Unrealized gain on investments	20	12	39	17
Gain on derivatives	8,504	4,621	10,639	35,412
Foreign currency translation	(231)	(4,027)	8	(7,370)
Other comprehensive income, net of tax	8,293	606	10,686	28,059
Total comprehensive income	44,752	22,411	71,340	47,420
Less: Comprehensive income attributable to noncontrolling interests	82	1,140	2,343	855
Comprehensive income attributable to McDermott International, Inc.	$ 44,670	$ 21,271	$ 68,997	$ 46,565