Accumulated Other Comprehensive Income (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Accumulated Other Comprehensive Income/(Loss) [Roll Forward]
Foreign currency translation adjustment, beginning balance	$ (14,687,000)
Foreign currency translation adjustment, other comprehensive income before reclassifications	3,754,000
Foreign currency translation adjustment, amounts reclassified from accumulated other comprehensive income	0
Foreign currency translation adjustment, current period change	3,754,000	(5,346,000)
Foreign currency translation adjustment, ending balance	(10,933,000)
Defined benefit plans, beginning balance	214,000
Defined benefit plans, other comprehensive income before reclassifications	67,000
Defined benefit plans, amounts reclassified from accumulated other comprehensive income	0
Defined benefit plans, current period change	67,000	98,000
Defined benefit plans, ending balance	281,000
Net unrealized gain on cash flow hedges, beginning balance	20,562,000
Net unrealized loss on cash flow hedges, current period change	(6,959,000)	4,437,000
Net unrealized gain on cash flow hedges, ending balance	13,603,000
Accumulated other comprehensive income, beginning balance	6,089,000
Accumulated other comprehensive loss, current period change	(3,138,000)	(811,000)
Accumulated other comprehensive income, ending balance	2,951,000
Designated as hedging instrument [Member] | Interest rate swap [Member]
Accumulated Other Comprehensive Income/(Loss) [Roll Forward]
Net unrealized loss on cash flow hedges, other comprehensive income before reclassifications	(6,694,000)
Net unrealized loss on cash flow hedges reclassed from accumulated other comprehensive income	(265,000)
Net unrealized gain on cash flow hedges, amounts reclassified from AOCI on derivatives, tax benefit	176,000
Net unrealized loss on cash flow hedges, current period change	(6,959,000)	4,437,000
OCI before reclassifications [Member]
Accumulated Other Comprehensive Income/(Loss) [Roll Forward]
Accumulated other comprehensive loss, current period change	(2,873,000)
Reclassified from accumulated OCI [Member]
Accumulated Other Comprehensive Income/(Loss) [Roll Forward]
Accumulated other comprehensive loss, current period change	$ (265,000)