Condensed Consolidated Statements of Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenues:
Premium income	$ 66,357	$ 75,391	$ 244,678	$ 203,478
Fee income	163,331	135,160	319,223	262,103
Other revenue			7,355
Net investment income	299,179	299,792	589,581	602,921
Realized investment gains (losses), net:
Total other-than-temporary impairments	359		(61)	(254)
Other-than-temporary impairments transferred to other comprehensive income (loss)			(434)
Other realized investment gains, net	(1,353)	24,919	20,998	37,053
Total realized investment gains (losses), net	(994)	24,919	20,503	36,799
Total revenues	527,873	535,262	1,181,340	1,105,301
Benefits and expenses:
Life and other policy benefits	164,044	179,545	309,636	360,454
Increase (decrease) in future policy benefits	(32,985)	(57,657)	12,286	(58,288)
Interest paid or credited to contractholders	121,796	130,400	248,727	257,689
Provision for policyholders' share of earnings on participating business	(483)	558	4,496	2,188
Dividends to policyholders	12,868	11,775	34,720	32,725
Total benefits, net	265,240	264,621	609,865	594,768
General insurance expenses	172,728	151,858	340,152	291,615
Amortization of deferred acquisition costs and value of business acquired	16,783	15,789	32,881	31,231
Interest expense	9,335	9,351	18,673	18,690
Total benefits and expenses, net	464,086	441,619	1,001,571	936,304
Income before income taxes	63,787	93,643	179,769	168,997
Income tax expense	20,374	32,595	62,129	56,955
Net income	$ 43,413	$ 61,048	$ 117,640	$ 112,042