Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Beginning balance			$ 52,230
Other comprehensive income before reclassifications			(780)
Amounts reclassified from accumulated other comprehensive income			1,081
Other comprehensive income (loss)	$ (56)	$ 5,488	301	$ 10,170
Ending balance	52,531		52,531
Foreign Currency [Member]
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Beginning balance			390
Other comprehensive income before reclassifications			(673)
Amounts reclassified from accumulated other comprehensive income			0
Other comprehensive income (loss)			(673)
Ending balance	(283)		(283)
Unrealized holding gains on available-for-sale securities [Member]
Changes in Accumulated Other Comprehensive Income by Component [Roll Forward]
Beginning balance			51,840
Other comprehensive income before reclassifications			(107)
Amounts reclassified from accumulated other comprehensive income			1,081
Other comprehensive income (loss)			974
Ending balance	$ 52,814		$ 52,814