Fair Value Measurements (Financial Instruments Not Carried at Fair Value) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Assets not carried at fair value [Abstract]
Policy loans, at outstanding balance	$ 1,951		$ 1,952
Mortgage loans (net of allowances for loan losses of $1)	4,935		4,182
Level 3 [Member]
Assets not carried at fair value [Abstract]
Policy loans, at outstanding balance	1,951		1,952
Mortgage loans (net of allowances for loan losses of $1)	4,935		4,182
Liabilities not carried at fair value [Abstract]
Other policyholder funds and benefits payable	9,318	[1]	10,065	[1]
Consumer notes	159	[2]	310	[2]
Policy loans [Member] | Level 3 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Loans Receivable, Fair Value Disclosure	2,112		2,099
Mortgage Loans [Member] | Level 3 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Loans Receivable, Fair Value Disclosure	5,109		4,382
Other policyholder funds and benefits payable [Member] | Level 3 [Member]
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Notes Payable, Fair Value Disclosure	9,668	[1]	10,959	[1]
Consumer Notes [Member] | Level 3 [Member]
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Notes Payable, Fair Value Disclosure	$ 159	[2]	$ 305	[2]

[1] Excludes group accident and health and universal life insurance contracts, including corporate owned life insurance.

[2] Excludes amounts carried at fair value and included in disclosures above.