Summary of Significant Accounting Policies (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Components of accumulated other comprehensive loss, net of tax
Balance at the beginning of the period	$ (3,781)	$ (25)	$ (1,423)
Change during the period	2,126	(3,756)	1,398
Balance at the end of the period	(1,655)	(3,781)	(25)
Unrealized Gain (Loss) on derivatives | Foreign Currency
Components of accumulated other comprehensive loss, net of tax
Balance at the beginning of the period	(284)
Change during the period	657	(284)
Balance at the end of the period	373	(284)
Unrealized Gain (Loss) on derivatives | Interest Rate Swaps
Components of accumulated other comprehensive loss, net of tax
Balance at the beginning of the period			(1,362)
Change during the period			1,362
Unrealized Gain (Loss) on Available for Sale Securities
Components of accumulated other comprehensive loss, net of tax
Balance at the beginning of the period	275
Change during the period	(279)	275
Balance at the end of the period	(4)	275
Foreign Currency Translation
Components of accumulated other comprehensive loss, net of tax
Balance at the beginning of the period	(3,772)	(25)	(61)
Change during the period	1,748	(3,747)	36
Balance at the end of the period	$ (2,024)	$ (3,772)	$ (25)