Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows - operating activities
Premiums collected	$ 661,094	$ 668,582	$ 667,524
Policyholder benefits paid	(549,888)	(496,339)	(479,484)
Policy acquisition and other operating expenses paid	(241,138)	(232,363)	(221,920)
Federal income taxes paid	(4,130)	(25,049)	(6,577)
Investment income collected	280,963	270,468	240,555
Interest expense paid	(13,515)	(13,605)	(14,052)
Contribution to defined benefit pension plan trust fund	(5,926)	(1,307)	(2,700)
Other	(11,581)	(12,633)	(4,444)
Net cash provided by operating activities	115,879	157,754	178,902
Cash flows - investing activities
Purchases	(1,356,092)	(1,711,091)	(2,018,457)
Sales	588,987	709,381	1,445,053
Maturities, paydowns, calls and redemptions	361,132	573,495	353,301
Net cash provided by (used in) short-term and other investments	102,966	124,141	(47,809)
Net cash used in investing activities	(303,007)	(304,074)	(267,912)
Cash flows - financing activities
Dividends paid to shareholders	(18,990)	(14,288)	(9,635)
Acquisition of treasury stock	(2,047)
Exercise of stock options	2,127	4,167
Principal borrowings on Bank Credit Facility
Annuity contracts, variable and fixed
Deposits	433,896	395,469	349,804
Benefits, withdrawals and net transfers to Separate Account (variable annuity) assets	(219,415)	(244,673)	(245,719)
Life policy accounts
Deposits	2,078	2,060	1,762
Withdrawals and surrenders	(5,343)	(5,015)	(5,475)
Change in bank overdrafts	(3,654)	6,680	(3,083)
Net cash provided by financing activities	188,652	144,400	87,654
Net increase (decrease) in cash	1,524	(1,920)	(1,356)
Cash at beginning of period	5,928	7,848	9,204
Cash at end of period	$ 7,452	$ 5,928	$ 7,848