Fair Value Of Financial Instruments (Changes In Fair Value Included In the Company's Consolidated Income Statement) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Fixed Maturity Securities Held At Fair Value [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange	$ (484)	$ 374
Other Assets [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange		26
Long-Term Debt [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange	594	(661)
Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange	(19)	(26)
Residential Mortgage Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange	(143)	295
Loan Repurchase Commitments [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net Gains (Losses) on Financial Instruments at Fair Value and Foreign Exchange	$ 242	$ 336