CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Revenues	$ 550,463	$ 603,811
Costs and Expenses:
Cost of operations	475,459	591,493
Selling, general and administrative expenses	51,676	51,964
Gain on disposal of assets	(367)	(6,439)
Restructuring expenses	10,389	6,125
Total costs and expenses	537,157	643,143
(Loss) Income from Investments in Unconsolidated Affiliates	(6,741)	1,123
Operating Income (Loss)	6,565	(38,209)
Other Income (Expense):
Interest income (expense), net	(12,179)	61
Loss on foreign currency, net	(1,468)	(4,082)
Other expense, net	(97)	(265)
Total other expense	(13,744)	(4,286)
Loss before provision for income taxes and noncontrolling interests	(7,179)	(42,495)
Provision for income taxes	4,869	3,489
Net loss	(12,048)	(45,984)
Less: net income attributable to noncontrolling interest	2,459	536
Net loss attributable to McDermott International, Inc.	$ (14,507)	$ (46,520)
Net loss attributable to McDermott International, Inc.:
Basic	$ (0.06)	$ (0.20)
Diluted	$ (0.06)	$ (0.20)
Shares used in the computation of losses per share:
Basic:	237,504,719	236,961,158
Diluted:	237,504,719	236,961,158