Invested Assets (Details 1) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Amortized cost and fair value of fixed maturities by contractual maturity [Abstract]
Due in one year or less, Amortized cost	$ 1,991
Due after one year through five years, Amortized cost	11,536
Due after five years through ten years, Amortized cost	11,870
Due after ten years, Amortized cost	7,387
Subtotal fixed maturities, Amortized cost	32,784
Due in one year or less, Fair value	2,023
Due after one year through five years, Fair value	12,102
Due after five years through ten years, Fair value	12,647
Due after ten years, Fair value	7,601
Subtotal fixed maturities, Fair value	34,373
Taxable, Amortized cost	16,440	15,989
Taxable, Fair value	17,203	16,745
Total fixed maturities, Amortized cost	35,656	35,061
Total fixed maturities, Fair value	37,367	36,519
Residential Mortgage-Backed Securities [Member]
Amortized cost and fair value of fixed maturities by contractual maturity [Abstract]
Taxable, Amortized cost	1,061	1,293
Taxable, Fair value	1,108	1,350
Commercial Mortgage-Backed Securities [Member]
Amortized cost and fair value of fixed maturities by contractual maturity [Abstract]
Taxable, Amortized cost	1,811	1,688
Taxable, Fair value	$ 1,886	$ 1,757

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This item represents total fixed maturities that are categorized as neither held-to-maturity nor trading. Such securities are reported at fair value; unrealized gains and losses of such securities are excluded from earnings and included in other comprehensive income.

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- Definition

This item represents the amortized cost basis of investments in debt securities having predetermined or determinable maturity dates.

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This item represents total taxable debt securities that are categorized as neither held-to-maturity nor trading. Such securities are reported at fair value; unrealized gains and losses of such securities are excluded from earnings and included in other comprehensive income.

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This item represents the amortized cost basis of taxable debt securities that are categorized as neither held-to-maturity nor trading.

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This item represents debt securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are expected to mature after five years and through ten years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS115-1/124-1
-Paragraph 7
-Footnote 2

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 20
-Subparagraph c

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This item represents the fair value of debt securities which are expected to mature after five years and through ten years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 20
-Subparagraph c

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This item represents debt securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are expected to mature after one year and through five years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

+ References

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This item represents the fair value of debt securities which are expected to mature after one year and through five years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 20
-Subparagraph b

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This item represents debt securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are expected to mature after ten years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

+ References

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This item represents the fair value of debt securities which are expected to mature after ten years from the balance sheet date which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 20
-Subparagraph d

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This item represents the total of all debt securities grouped by maturity dates, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are classified neither as held-to-maturity nor trading securities.

+ References

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This item represents the total of all debt securities grouped by maturity dates, at fair value, which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 20

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This item represents debt securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are expected to mature within one year of the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

+ References

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This item represents the fair value of debt securities which are expected to mature within one year of the balance sheet date and which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 20
-Subparagraph a

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