CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 7,534	$ (25,946)	$ 9,176	$ (77,628)
Other comprehensive income (loss), net of tax:
Unrealized gain (loss) on investments	(27)	(7)	(11)
Foreign currency translation adjustment	(9,333)	(1,454)	(16,319)	(2,714)
Gain (loss) on derivatives	(701)	(32,930)	9,973	(17,664)
Other comprehensive loss, net of tax	(10,061)	(34,391)	(6,357)	(20,378)
Total comprehensive income (loss)	(2,527)	(60,337)	2,819	(98,006)
Less: comprehensive income attributable to non-controlling interests	3,868	4,290	8,411	6,494
Comprehensive loss attributable to McDermott International, Inc.	$ (6,395)	$ (64,627)	$ (5,592)	$ (104,500)