Schedule II Condensed Financial Information of Registrant (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues
Net investment income													$ 313,610	$ 306,003	$ 288,311
Realized investment gains													22,245	27,298	37,663
Total revenues	259,215	251,884	265,637	254,531	255,417	256,548	254,226	244,623	247,645	260,833	245,351	244,473	1,031,267	1,010,814	998,302
Expenses
Interest													14,236	14,249	14,007
Total expenses													877,201	861,641	903,384
Income tax benefit													43,173	45,307	24,412
Net income	34,287	23,599	25,995	27,012	31,826	32,266	13,103	26,671	32,913	23,637	(11,851)	25,807	110,893	103,866	70,506
Parent Company [Member]
Revenues
Net investment income													6	2	(3)
Realized investment gains													208	0	0
Total revenues													214	2	(3)
Expenses
Interest													14,236	14,249	14,007
Other													4,832	4,576	3,590
Total expenses													19,068	18,825	17,597
Loss before income tax benefit and equity in net earnings of subsidiaries													(18,854)	(18,823)	(17,600)
Income tax benefit													(6,599)	(6,196)	(8,197)
Loss before equity in net earnings of subsidiaries													(12,255)	(12,627)	(9,403)
Equity in net earnings of subsidiaries													123,148	116,493	79,909
Net income													$ 110,893	$ 103,866	$ 70,506