Income Taxes (Components of Income (Loss) from Continuing Operations Before Income Taxes and Income Tax Expense) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income (loss) from continuing operations before income taxes
United States									$ (595,196)	$ (1,259,268)	$ 179,484
Foreign									102,081	(2,022,994)	1,072,786
Income (loss) from continuing operations before income taxes	$ (80,100)	$ (16,700)	$ (131,300)	$ (265,000)	$ (646,500)	$ (2,408,000)	$ (110,100)	$ (117,700)	(493,115)	(3,282,262)	1,252,270
Income tax expense (benefit)
Federal - Current										(9,435)	25,151
Federal - Deferred									(197,450)	(241,127)	25,444
Total Federal income tax expense (benefit)									(197,450)	(250,562)	50,595
State									13,984	(5,294)	8,840
Foreign - Current									146,861	(40,550)	359,502
Foreign - Deferred									(182,567)	(730,084)	(191,640)
Total Foreign income tax expense (benefit)									(35,706)	(770,634)	167,862
Total income tax expense (benefit)									$ (219,172)	$ (1,026,490)	$ 227,297