Reinsurance (Details 1) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Assets:
Premiums and Other Receivables, Net	$ 22,481	$ 19,799
Deferred policy acquisition costs and value of business acquired	27,971	27,092	19,083	20,001
Total assets	50,452	46,891
Liabilities:
Future policy benefits	184,252	170,912
Policyholder account balances	217,700	210,757	138,515
Other policy-related balances	15,599	15,750
Other Liabilities	30,914	20,366
Total liabilities	448,465	417,785
Assumed Reinsurance [Member]
Assets:
Premiums and Other Receivables, Net	641	722
Deferred policy acquisition costs and value of business acquired	138	176
Total assets	779	898
Liabilities:
Future policy benefits	1,972	2,074
Policyholder account balances	3,494	2,237
Other policy-related balances	339	265
Other Liabilities	630	608
Total liabilities	6,435	5,184
Ceded Reinsurance [Member]
Assets:
Premiums and Other Receivables, Net	16,239	13,560
Deferred policy acquisition costs and value of business acquired	(146)	(179)
Total assets	16,093	13,381
Liabilities:
Future policy benefits	(1)	(65)
Policyholder account balances	0	0
Other policy-related balances	380	504
Other Liabilities	5,039	2,701
Total liabilities	5,418	3,140
Direct Reinsurance [Member]
Assets:
Premiums and Other Receivables, Net	5,601	5,517
Deferred policy acquisition costs and value of business acquired	27,979	27,095
Total assets	33,580	32,612
Liabilities:
Future policy benefits	182,281	168,903
Policyholder account balances	214,206	208,520
Other policy-related balances	14,880	14,981
Other Liabilities	25,245	17,057
Total liabilities	$ 436,612	$ 409,461