Reinsurance (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Premiums written, net, consolidated [Abstract]
Direct insurance premiums and fees	$ 6,997,000,000	$ 6,599,000,000	$ 6,124,000,000
Reinsurance assumed	10,000,000	13,000,000	10,000,000
Reinsurance ceded	(1,276,000,000)	(1,202,000,000)	(1,148,000,000)
Total insurance premiums and fees	5,731,000,000	5,410,000,000	4,986,000,000
Policyholder benefits and claims incurred, net [Abstract]
Direct insurance benefits	4,897,000,000	4,547,000,000	3,891,000,000
Reinsurance recoveries netted against benefits	(1,552,000,000)	(1,220,000,000)	(1,057,000,000)
Total benefits	3,345,000,000	3,327,000,000	2,834,000,000
Percent of mortality risk reinsured on newly issued non-term life insurance contracts, low end	25.00%
Percent of mortality risk reinsured on newly issued non-term life insurance contracts, high end	30.00%
Percent of total mortality risk reinsured, including term insurance contracts, low end	30.00%
Percent of total mortality risk reinsured, including term insurance contracts, high end	35.00%
Maximum retention per single insured life on fixed and VUL insurance contracts	11,000,000
Maximum retention per single insured life for term life insurance and for corporate-owned life insurance contracts	1,000,000
Reserves associated with modified coinsurance reinsurance arrangements	878,000,000
Ceded Credit Risk, Amount [Abstract]
Liabilities for funds withheld	1,045,000,000	1,149,000,000
Swiss Re [Member]
Ceded Credit Risk, Amount [Abstract]
Reinsurance receivable	2,800,000,000	3,000,000,000
Trust funded by Swiss Re to support reinsurance receivable	2,200,000,000
Liabilities for funds withheld	1,000,000,000
Liabilities for reinsurance related embedded derivatives	142,000,000
Amortization period (in years) of deferred gain on business sold to Swiss Re	15
Amount of amortization, after-tax, of deferred gain on business sold to Swiss Re	$ 49,000,000	$ 49,000,000	$ 50,000,000