CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands		3 Months Ended												12 Months Ended
		Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	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, 2016	Dec. 31, 2015	Dec. 31, 2014
Comprehensive income (loss)
Net income		$ 19,823	$ 26,923	$ 11,866	$ 25,153	$ 21,040	$ 21,984	$ 16,183	$ 34,275	$ 30,068	$ 25,357	$ 20,452	$ 28,366	$ 83,765	$ 93,482	$ 104,243
Other comprehensive income (loss), net of taxes:
Change in net unrealized investment gains and losses on fixed maturities and equity securities	[1],[2]													571	(122,387)	163,564
Change in net funded status of benefit plans	[1]													(23)	1,159	(1,177)
Other comprehensive income (loss)	[1]													548	(121,228)	162,387
Total														$ 84,313	$ (27,746)	$ 266,630

[1] All amounts are net of tax.

[2] The pretax amounts reclassified from accumulated other comprehensive income, $5,176, $11,667 and $10,943, are included in net realized investment gains and losses and the related tax expenses, $1,812, $4,083 and $3,830, are included in income tax expense in the Consolidated Statements of Operations for the years ended December 31, 2016, 2015 and 2014, respectively.