Investments and Derivative Instruments (Details 4) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Available-for-sale Securities, Amortized Cost
One year or less, amortized cost	$ 2,127
Over one year through five years, amortized cost	15,678
Over five years through ten years, amortized cost	14,566
Over ten years, amortized cost	27,328
Subtotal, amortized cost	59,699
Mortgage-backed and asset-backed securities, amortized cost	20,322
Total fixed maturities, AFS, amortized cost	80,021
Available-for-sale Securities, Fair Value
One year or less, fair value	2,146
Over one year through five years, fair value	16,520
Over five years through ten years, fair value	15,712
Over ten years, fair value	29,280
Subtotal, fair value	63,658
Mortgage-backed and asset-backed securities, fair value	19,499
Total fixed maturities, AFS, fair value	$ 83,157	$ 81,809

Available for sale securities debt maturities before mortgage backed and asset backed securities amortized cost.

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