Accumulated Other Comprehensive Loss (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Changes in the components of accumulated other comprehensive income (loss)
Balance at beginning of the period	$ (2,975)
Other comprehensive income (loss) before reclassifications	(520)
Other comprehensive income (loss), net of tax	(520)	1,005
Balance at end of the period	(3,495)
Cumulative Translation
Changes in the components of accumulated other comprehensive income (loss)
Balance at beginning of the period	(2,976)
Other comprehensive income (loss) before reclassifications	(528)
Other comprehensive income (loss), net of tax	(528)
Balance at end of the period	(3,504)
Unrealized gains on available for sale securities
Changes in the components of accumulated other comprehensive income (loss)
Balance at beginning of the period	1
Other comprehensive income (loss) before reclassifications	8
Other comprehensive income (loss), net of tax	8
Balance at end of the period	$ 9