Accumulated Other Comprehensive Loss - Changes in Accumulated Other Comprehensive Loss (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ (6,217)	$ (4,216)
Other comprehensive income (loss) before reclassification	(1,615)	(2,863)	237
Amounts reclassified from accumulated other comprehensive income (loss)	861	862	862
Other comprehensive income (loss), net of tax	(754)	(2,001)	2,585
Ending balance	(6,971)	(6,217)	(4,216)
Loss on Cash Flow Hedge [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(5,745)	(6,607)
Other comprehensive income (loss) before reclassification	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	861	862
Other comprehensive income (loss), net of tax	861	862
Ending balance	(4,884)	(5,745)
Foreign Currency Items [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(472)	2,391
Other comprehensive income (loss) before reclassification	(1,615)	(2,863)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Other comprehensive income (loss), net of tax	(1,615)	(2,863)
Ending balance	$ (2,087)	$ (472)