Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 29,717us-gaap_NetIncomeLoss	$ 36,588us-gaap_NetIncomeLoss	$ 31,919us-gaap_NetIncomeLoss
Unrealized net gains on securities:
Unrealized holding net gains arising during the period	7,835	23,711	10,148
Less: reclassification adjustment for net gains included in net income	(5,084)	(10,089)	(1,273)
Change in unrealized gains on investments	2,751	13,622	8,875
Foreign currency translation adjustments	(1,011)	(575)	217
Other comprehensive income	1,740	13,047	9,092
Comprehensive income	$ 31,457	$ 49,635	$ 41,011

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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