Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue	$ 2,271,603	$ 3,062,754	$ 3,659,624
Cost of services and products	1,992,376	2,457,325	2,800,423
Gross Margin	279,227	605,429	859,201
Selling, general and administrative expense	208,463	231,619	230,871
Income from Operations	70,764	373,810	628,330
Interest income	3,900	607	293
Interest expense, net of amounts capitalized	(25,318)	(25,050)	(4,708)
Equity earnings of unconsolidated affiliates	244	2,230	(51)
Other income (expense), net	(6,244)	(15,336)	(387)
Income before Income Taxes	43,346	336,261	623,477
Provision for income taxes	18,760	105,250	195,148
Net Income	$ 24,586	$ 231,011	$ 428,329
Cash Dividends declared per Share	$ 0.96	$ 1.08	$ 1.03
Basic Earnings per Share	$ 0.25	$ 2.35	$ 4.02
Weighted Average Number of Shares Outstanding, Basic	98,035	98,417	106,593
Diluted Earnings per Share	$ 0.25	$ 2.34	$ 4.00
Weighted Average Number of Shares Outstanding, Diluted	98,424	98,808	107,091
Norway Member
Other income (expense), net	$ (1,100)