Income Taxes - Change in Unrecognized Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Change in unrecognized tax benefits
Balance as of January 1	$ 188,376	$ 201,338	$ 47,552
Additions based on tax positions related to the current year		384	167,107
Additions for tax positions of prior years	3,873		1,744
Reductions for tax positions of prior years	(11,547)	(9,234)	(6,843)
Settlements	(1,447)	(4,112)	(8,222)
Balance as of December 31	179,255	188,376	201,338
Unrecognized Tax Benefits, Decrease Resulting from Foreign Currency Translation	2,100	2,000
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations		1,100
Additions based on tax positions related to the current year due to internal restructuring			166,000
Reductions for tax positions for prior years due to expiration of statutes		1,100
Interest and penalties on unrecognized tax benefits	9,200	7,400	19,200
Liability related to unrecognized tax benefit for accrued interest and penalties	600	1,400	6,100
Canada, Trinidad and U.S
Change in unrecognized tax benefits
Settlements	(6,000)
Colombia, Ecuador, Canada and Montana
Change in unrecognized tax benefits
Settlements		$ (5,000)
Algeria Canada And Oman Settlements
Change in unrecognized tax benefits
Settlements			$ (7,600)
Australia Algeria And Mexico
Change in unrecognized tax benefits
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations	7,200
Reductions for tax positions for prior years due to expiration of statutes	7,200
Trinidad [Member]
Change in unrecognized tax benefits
Settlements	$ (2,000)