Equity (Details 1) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss)
Beginning balance	$ (139,805)	$ (81,007)
Other comprehensive (loss) income before reclassifications	20,170	(65,142)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(579)	(845)
Net current-period Other comprehensive income (loss)	19,591	(65,987)
Net current-period Other comprehensive income attributable to noncontrolling interests	(911)	1,224
Ending balance	(121,125)	(145,770)
Interest Expense
Accumulated Other Comprehensive Income (Loss)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	1,801	2,284
Other income and (expense)
Accumulated Other Comprehensive Income (Loss)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(2,380)	(3,129)
Gains and Losses on Derivative Instruments
Accumulated Other Comprehensive Income (Loss)
Beginning balance	28,200	7,311
Other comprehensive (loss) income before reclassifications	(11,165)	23,581
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(579)	(845)
Net current-period Other comprehensive income (loss)	(11,744)	22,736
Net current-period Other comprehensive income attributable to noncontrolling interests	0	0
Ending balance	16,456	30,047
Gains and Losses on Derivative Instruments | Interest Expense
Accumulated Other Comprehensive Income (Loss)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	1,801	2,284
Gains and Losses on Derivative Instruments | Other income and (expense)
Accumulated Other Comprehensive Income (Loss)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(2,380)	(3,129)
Gains and Losses on Marketable Securities
Accumulated Other Comprehensive Income (Loss)
Beginning balance	(77)	(106)
Other comprehensive (loss) income before reclassifications	7	7
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
Net current-period Other comprehensive income (loss)	7	7
Net current-period Other comprehensive income attributable to noncontrolling interests	0	0
Ending balance	(70)	(99)
Gains and Losses on Marketable Securities | Interest Expense
Accumulated Other Comprehensive Income (Loss)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
Gains and Losses on Marketable Securities | Other income and (expense)
Accumulated Other Comprehensive Income (Loss)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss)
Beginning balance	(167,928)	(88,212)
Other comprehensive (loss) income before reclassifications	31,328	(88,730)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
Net current-period Other comprehensive income (loss)	31,328	(88,730)
Net current-period Other comprehensive income attributable to noncontrolling interests	(911)	1,224
Ending balance	(137,511)	(175,718)
Foreign Currency Translation Adjustments | Interest Expense
Accumulated Other Comprehensive Income (Loss)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0	0
Foreign Currency Translation Adjustments | Other income and (expense)
Accumulated Other Comprehensive Income (Loss)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	$ 0	$ 0