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
Net income	$ 69,178us-gaap_NetIncomeLoss	$ 62,764us-gaap_NetIncomeLoss	$ 89,405us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Change in unrealized gains on securities, net of taxes of $(55,020) $75,389, and $(53,838), respectively	102,176	(140,008)	99,986
Change in other-than-temporary impairment gains (losses) recognized in other comprehensive income, net of taxes of $(830), $259, and $(1,881), respectively	1,541	(481)	3,493
Total other comprehensive income (loss)	103,717	(140,489)	103,479
Total comprehensive income (loss)	$ 172,895us-gaap_ComprehensiveIncomeNetOfTax	$ (77,725)us-gaap_ComprehensiveIncomeNetOfTax	$ 192,884us-gaap_ComprehensiveIncomeNetOfTax

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

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