Income Taxes - Uncertain Tax Positions - Tabular Reconciliation (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized Tax Benefits, Beginning Balance	$ 12,719	$ 10,464	$ 10,686
Increase in Unrecognized Tax Benefits Taken in Prior Periods	0	1,597	0
(Decrease) in unrecognized tax benefits taken in prior periods	(411)	0	0
Increase in Unrecognized Tax Benefits Taken in Current Period	1,733	2,623	2,249
(Decrease) in Unrecognized Tax Benefits Due to Lapse of Statute of Limitations	(1,837)	(1,578)	(1,828)
Increase (Decrease) Due to Foreign Exchange Rates	206	(387)	(643)
Unrecognized Tax Benefits, Ending Balance	$ 12,410	$ 12,719	$ 10,464