Fair Value Measurements (Details 2) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010	Dec. 31, 2009
Assets:
Cash and cash equivalents	$ 991	$ 1,099	$ 1,140	$ 1,120
Equity securities	930	690
Mortgage loans	384	468
Policy loans	253	264
Assets of managed investment entities	2,439	2,537
Variable annuity assets (separate accounts)	515	616
Liabilities:
Long-term debt	937	952
Liabilities of managed investment entities	2,229	2,323
Variable annuity liabilities (separate accounts)	515	616
Carrying Value [Member]
Assets:
Cash and cash equivalents	991	1,099
Fixed maturities	21,993	19,721
Equity securities	930	690
Mortgage loans	384	468
Policy loans	253	264
Other investments - derivatives	47	98
Assets of managed investment entities	2,439	2,537
Variable annuity assets (separate accounts)	515	616
Liabilities:
Annuity benefits accumulated	14,582	12,696
Long-term debt	937	952
Liabilities of managed investment entities	2,229	2,323
Variable annuity liabilities (separate accounts)	515	616
Other liabilities - derivatives	24	14
Fair Value [Member]
Assets:
Cash and cash equivalents	991	1,099
Fixed maturities	21,993	19,721
Equity securities	930	690
Mortgage loans	387	469
Policy loans	253	264
Other investments - derivatives	47	98
Assets of managed investment entities	2,439	2,537
Variable annuity assets (separate accounts)	515	616
Liabilities:
Annuity benefits accumulated	14,437	12,233
Long-term debt	1,023	1,023
Liabilities of managed investment entities	2,229	2,323
Variable annuity liabilities (separate accounts)	515	616
Other liabilities - derivatives	$ 24	$ 14

Annuity Benefits Accumulated Excluding Life Contingent Annuities.

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Gross amount of loans made to policy and contract holders using their life insurance contracts' cash value or separate accounts as collateral.

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