Condensed Consolidated Statements of Earnings (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Premiums and other revenues:
Universal life and annuity contract charges	$ 36,602	$ 33,523	$ 112,824	$ 111,785
Traditional life premiums	4,506	4,159	13,946	13,241
Net investment income	110,966	141,403	374,596	451,904
Other revenues	5,377	5,822	16,351	17,954
Net realized investment gains (losses):
Total other-than-temporary impairment (“OTTI”) gains (losses)	0	214	(32)	524
Portion of OTTI (gains) losses recognized in other comprehensive income	0	(227)	(3)	(776)
Net OTTI losses recognized in earnings	0	(13)	(35)	(252)
Other net investment gains (losses)	2,169	3,298	6,782	7,451
Total net realized investment gains (losses)	2,169	3,285	6,747	7,199
Total condensed consolidated premiums and other revenues	159,620	188,192	524,464	602,083
Benefits and expenses:
Life and other policy benefits	13,163	16,941	40,922	48,081
Amortization of deferred policy acquisition costs	23,467	24,244	79,304	83,900
Universal life and annuity contract interest	59,211	87,486	224,576	299,224
Other operating expenses	20,451	22,675	63,414	69,442
Total benefits and expenses	116,292	151,346	408,216	500,647
Earnings before Federal income taxes	43,328	36,846	116,248	101,436
Federal income taxes	14,862	12,064	38,773	33,031
Net earnings	28,466	24,782	77,475	68,405
Common Class A [Member]
Benefits and expenses:
Net earnings	27,661	24,081	75,284	66,470
Basic earnings per share:
Earnings Per Share, Basic (in dollars per share)	$ 8.05	$ 7.01	$ 21.92	$ 19.35
Diluted earnings per share:
Earnings Per Share, Diluted (in dollars per share)	$ 8.05	$ 7.00	$ 21.91	$ 19.32
Common Class B [Member]
Benefits and expenses:
Net earnings	$ 805	$ 701	$ 2,191	$ 1,935
Basic earnings per share:
Earnings Per Share, Basic (in dollars per share)	$ 4.03	$ 3.51	$ 10.95	$ 9.68
Diluted earnings per share:
Earnings Per Share, Diluted (in dollars per share)	$ 4.03	$ 3.51	$ 10.95	$ 9.68