CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands		3 Months Ended												12 Months Ended
		Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Comprehensive income (loss)
Net income		$ 21,040	$ 21,984	$ 16,183	$ 34,275	$ 30,068	$ 25,357	$ 20,452	$ 28,366	$ 34,287	$ 23,599	$ 25,995	$ 27,012	$ 93,482	$ 104,243	$ 110,893
Other comprehensive income (loss), net of taxes:
Change in net unrealized gains and losses on fixed maturities and equity securities	[1],[2]													(122,387)	163,564	(248,410)
Change in net funded status of pension and other postretirement benefit obligations	[1]													1,159	(1,177)	3,535
Other comprehensive income (loss)	[1]													(121,228)	162,387	(244,875)
Total														$ (27,746)	$ 266,630	$ (133,982)

[1] All amounts are net of tax.

[2] The pretax amounts reclassified from accumulated other comprehensive income, $11,667, $10,943 and $22,245, are included in net realized investment gains and losses and the related tax expenses, $4,083, $3,830 and $7,786, are included in income tax expense in the Consolidated Statements of Operations for the years ended December 31, 2015, 2014 and 2013, respectively.