Unaudited Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Unaudited Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 6,243us-gaap_NetIncomeLoss	$ 6,361us-gaap_NetIncomeLoss
Unrealized net gains on securities:
Unrealized net gains arising during the period	622	5,834
Less: reclassification adjustment for net gains (losses) included in net income	(514)	651
Change in unrealized gains on investments	1,136	5,183
Foreign currency translation adjustments	(779)	(501)
Other comprehensive income	357	4,682
Comprehensive income	$ 6,600	$ 11,043

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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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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