Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 23,283	$ 29,717	$ 36,588
Unrealized net gains (losses) on securities:
Unrealized holding net gains (losses) arising during the period	(12,639)	7,835	23,711
Less: reclassification adjustment for net losses included in net income	(277)	(5,084)	(10,089)
Change in unrealized gains on investments	(12,916)	2,751	13,622
Foreign currency translation adjustments	(1,456)	(1,011)	(575)
Other comprehensive income (loss)	(14,372)	1,740	13,047
Comprehensive income	$ 8,911	$ 31,457	$ 49,635