Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net earnings	$ 92,558	$ 55,627	$ 72,897
Adjustments to reconcile net earnings to net cash provided by operating activities:
Universal life and annuity contract interest	262,339	232,788	266,603
Surrender charges and other policy revenues	(14,720)	(4,251)	(35,350)
Realized (gains) losses on investments	(13,201)	(6,082)	(6,932)
Accrual and amortization of investment income	(1,458)	(2,588)	(2,056)
Depreciation and amortization	5,688	5,251	4,727
(Increase) decrease in value of derivatives	(27,147)	33,335	(16,612)
(Increase) decrease in deferred policy acquisition and sales inducement costs	(10,623)	(65,073)	(124,191)
(Increase) decrease in accrued investment income	(4,790)	(8,155)	(8,148)
(Increase) decrease in other assets	(7,176)	(1,149)	(21,188)
Increase (decrease) in liabilities for future policy benefits	13,536	24,245	38,775
(Decrease) increase in other policyholder liabilities	(2,747)	(219)	22,597
(Decrease) increase in Federal income tax liability	(15,054)	(7,971)	(6,023)
(Decrease) increase in other liabilities	13,076	(11,104)	(6,230)
Other, net	0	111	(1)
Net cash provided by operating activities	290,281	244,765	178,868
Proceeds from sales of:
Securities held to maturity	0	0	0
Securities available for sale	8,214	19,522	32,545
Other investments	8,791	5,183	4,779
Proceeds from maturities and redemptions of:
Securities held to maturity	1,473,885	640,620	833,157
Securities available for sale	347,521	171,852	78,175
Derivatives, index options	54,745	82,204	80,497
Purchases of:
Securities held to maturity	(1,787,388)	(1,311,122)	(1,633,597)
Securities available for sale	(490,689)	(387,203)	(359,365)
Derivatives, index options	(56,413)	(65,029)	(54,254)
Other investments	(5,380)	(10,903)	(2,212)
Principal payments on mortgage loans	36,545	19,534	21,943
Cost of mortgage loans acquired	(21,454)	(35,980)	(63,762)
(Increase) decrease in policy loans	3,418	3,481	(112)
Net cash used in investing activities	(428,205)	(867,841)	(1,062,206)
Cash flows from financing activities:
Dividends on common stock	(1,273)	(1,273)	(1,270)
Deposits to account balances for universal life and annuity contracts	985,370	1,476,657	1,499,830
Return of account balances on universal life and annuity contracts	(841,126)	(813,766)	(643,911)
Issuance of common stock under stock option plan	0	633	463
Net cash provided by (used in) financing activities	142,971	662,251	855,112
Effect of foreign exchange	221	(217)	(308)
Net increase (decrease) in cash and short-term investments	5,271	38,958	(28,534)
Cash and short-term investments at beginning of period	119,290	80,332	108,866
Cash and short-term investments at end of period	124,561	119,290	80,332
Cash paid during the period for:
Interest	40	0	40
Income taxes	62,540	31,331	40,850
Noncash operating activities:
Deferral of sales inducements	$ 4,498	$ 16,890	$ 28,985