Changes in Accumulated Other Comprehensive Income (Loss) (Changes by Component)(Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated comprehensive income (loss) at beginning of period	$ (1,328,433)
Other comprehensive income (loss) before reclassifications	73,558	$ (720,570)	$ (956,130)
Amounts reclassified from accumulated other comprehensive loss	338,391	289,131	53,465
Total other comprehensive income (loss)	411,949	(431,439)	(902,665)
Accumulated comprehensive loss at end of period	(916,484)	(1,328,433)
Changes related to cash flow derivative hedges
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated comprehensive income (loss) at beginning of period	(1,232,073)	(826,026)	43,324
Other comprehensive income (loss) before reclassifications	73,973	(697,671)	(919,094)
Amounts reclassified from accumulated other comprehensive loss	337,250	291,624	49,744
Total other comprehensive income (loss)	411,223	(406,047)	(869,350)
Accumulated comprehensive loss at end of period	(820,850)	(1,232,073)	(826,026)
Changes in defined benefit plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated comprehensive income (loss) at beginning of period	(26,447)	(31,207)	(23,994)
Other comprehensive income (loss) before reclassifications	(2,777)	3,053	(8,937)
Amounts reclassified from accumulated other comprehensive loss	1,141	1,707	1,724
Total other comprehensive income (loss)	(1,636)	4,760	(7,213)
Accumulated comprehensive loss at end of period	(28,083)	(26,447)	(31,207)
Foreign currency translation adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated comprehensive income (loss) at beginning of period	(69,913)	(39,761)	(13,659)
Other comprehensive income (loss) before reclassifications	2,362	(25,952)	(28,099)
Amounts reclassified from accumulated other comprehensive loss	0	(4,200)	1,997
Total other comprehensive income (loss)	2,362	(30,152)	(26,102)
Accumulated comprehensive loss at end of period	(67,551)	(69,913)	(39,761)
AOCI including portion attributable to noncontrolling interest
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Accumulated comprehensive income (loss) at beginning of period	(1,328,433)	(896,994)	5,671
Accumulated comprehensive loss at end of period	$ (916,484)	$ (1,328,433)	$ (896,994)