Fair Value Measurements (Details 2) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010	Dec. 31, 2009
Assets:
Cash and cash equivalents	$ 1,629	$ 1,099	$ 1,011	$ 1,120
Equity securities	779	690
Mortgage loans	340	468
Policy loans	255	264
Assets of managed investment entities	2,591	2,537
Variable annuity assets (separate accounts)	624	616
Liabilities:
Long-term debt	940	952
Liabilities of managed investment entities	2,430	2,323
Variable annuity liabilities (separate accounts)	624	616
Carrying Value [Member]
Assets:
Cash and cash equivalents	1,629	1,099
Fixed maturities	20,895	19,721
Equity securities	779	690
Mortgage loans	340	468
Policy loans	255	264
Other investments - derivatives	113	98
Assets of managed investment entities	2,591	2,537
Variable annuity assets (separate accounts)	624	616
Liabilities:
Annuity benefits accumulated	13,915	12,696
Long-term debt	940	952
Liabilities of managed investment entities	2,430	2,323
Variable annuity liabilities (separate accounts)	624	616
Other liabilities - derivatives	18	14
Fair Value [Member]
Assets:
Cash and cash equivalents	1,629	1,099
Fixed maturities	20,895	19,721
Equity securities	779	690
Mortgage loans	349	469
Policy loans	255	264
Other investments - derivatives	113	98
Assets of managed investment entities	2,591	2,537
Variable annuity assets (separate accounts)	624	616
Liabilities:
Annuity benefits accumulated	13,512	12,233
Long-term debt	1,033	1,023
Liabilities of managed investment entities	2,430	2,323
Variable annuity liabilities (separate accounts)	624	616
Other liabilities - derivatives	$ 18	$ 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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