Accumulated Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Accumulated Other Comprehensive Income [Roll Forward]
Foreign Currency Translation Adjustment, Beginning Balance	$ 47,845
Foreign Currency Translation Adjustment, Current Period Change	(5,346)
Foreign Currency Translation Adjustment, Amounts reclassified from accumulated other comprehensive income	0
Foreign Currency Translation Adjustment,Current period change	(5,346)	6,246
Foreign Currency Translation Adjustment, Ending Balance	42,499
Defined Benefit Plans, Beginning Balance	(148)
Defined Benefit Plans, Other comprehensive income before reclassifications	98
Defined Benefit Plans, Amounts reclassified from accumulated other comprehensive income	0
Defined Benefit Plans, Current Period Change	98	(409)
Defined Benefit Plans, Ending Balance	(50)
Net Unrealized Losses on Cash Flow Hedges, Beginning Balance	(426)
Net unrealized gain on qualifying cash flow hedges, net of tax	4,437	446
Net Unrealized Losses on Cash Flow Hedges, Ending Balance	4,011
Accumulated Other Comprehensive Income, Beginning Balance	47,271
Accumulated Other Comprehensive Income, Current Period Change	(811)
Accumulated Other Comprehensive Income, Ending Balance	46,460
Designated as Hedging Instrument [Member] | Interest Rate Swap [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Net Unrealized Gain/(Loss) on Cash Flow Hedges, Other comprehensive income before reclassifications	3,717
Net loss on cash flow hedge reclassified from accumulated other comprehensive income	720
Net unrealized gain on qualifying cash flow hedges, net of tax	4,437	446
OCI before reclassifications [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income, Current Period Change	(1,531)
Reclassified from accumulated OCI [Member]
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated Other Comprehensive Income, Current Period Change	$ 720