Cumulative Other Comprehensive (Loss) Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013
Amounts recognized in cumulative other comprehensive (loss) income
Balance at beginning of period	$ 2,577	$ 565
Other comprehensive income (loss) before reclassifications	(36,385)	(35,596)
Amounts reclassified from cumulative other comprehensive income (loss) to net income	1,232	2,455
Net current period other comprehensive income (loss)	(35,153)	(33,141)
Balance at end of period	(32,576)	(32,576)
Unrealized Gain (Loss) on Derivative Instruments
Amounts recognized in cumulative other comprehensive (loss) income
Balance at beginning of period	(15,573)	(16,624)
Other comprehensive income (loss) before reclassifications	1,546	1,361
Amounts reclassified from cumulative other comprehensive income (loss) to net income	1,236	2,472
Net current period other comprehensive income (loss)	2,782	3,833
Balance at end of period	(12,791)	(12,791)
Foreign Currency Translation Adjustments
Amounts recognized in cumulative other comprehensive (loss) income
Balance at beginning of period	18,044	17,071
Other comprehensive income (loss) before reclassifications	(37,821)	(36,848)
Net current period other comprehensive income (loss)	(37,821)	(36,848)
Balance at end of period	(19,777)	(19,777)
Equity in Unrealized Gain (Loss) of an Investee
Amounts recognized in cumulative other comprehensive (loss) income
Balance at beginning of period	106	118
Other comprehensive income (loss) before reclassifications	(110)	(109)
Amounts reclassified from cumulative other comprehensive income (loss) to net income	(4)	(17)
Net current period other comprehensive income (loss)	(114)	(126)
Balance at end of period	$ (8)	$ (8)