Derivative Instruments (Balance Sheet Offsetting) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Financial Assets
Derivative Fair Value Of Derivative Asset	$ 3,102	$ 3,547
Derivative Instruments, Gross amount of recognized assets	1,805	3,547
Derivative Instruments, Gross amounts offset	(924)	(895)
Derivative Instruments, Net amount of assets	881	2,652
Derivative Instruments, Cash collateral received	(623)	(2,624)
Derivative Instruments, Net amount	258	28
Embedded Derivative Instruments, Gross amount of recognized assets	1,244
Embedded Derivative Instruments, Gross amounts offset
Embedded Derivative Instruments, Net amount of assets	1,244
Embedded Derivative Instruments, Cash collateral received
Embedded Derivative Instruments, Net amount	1,244
Securities Lending and Reverse Repurchase Agreements, Gross amount of recognized assets
Securities Lending and Reverse Repurchase Agreements, Gross amounts offset
Securities Lending and Reverse Repurchase Agreements, Net amount of assets
Securities Lending and Reverse Repurchase Agreements, Cash collateral received
Securities Lending and Reverse Repurchase Agreements, Net amount
Total, Gross amount of recognized assets	3,049	3,547
Total, Gross amounts offset	(924)	(895)
Total, Net amount of assets	2,125	2,652
Total, Cash collateral received	(623)	(2,624)
Total, Net amount	1,502	28
Securities Purchased under Agreements to Resell, Gross
Financial Liabilities
Derivative Fair Value Of Derivative Liability	2,322	2,762
Derivative Instruments, Gross amount of recognized liabilities	242	11
Derivative Instruments, Gross amounts offset	(55)
Derivative Instruments, Net amount of liabilities	187	11
Derivative Instruments, Financial instruments
Derivative Instruments, Net amount	187	11
Embedded Derivative Instruments, Gross amount of recognized liabilities	1,156	1,856
Embedded Derivative Instruments, Gross amounts offset
Embedded Derivative Instruments, Net amount of liabilities	1,156	1,856
Embedded Derivative Instruments, Financial instruments
Embedded Derivative Instruments, Net amount	1,156	1,856
Securities Lending and Reverse Repurchase Agreements, Gross amount of recognized liabilities	2,600	1,614
Securities Lending and Reverse Repurchase Agreements, Gross amounts offset
Securities Lending and Reverse Repurchase Agreements, Net amount of liabilities	2,600	1,614
Securities Lending and Reverse Repurchase Agreements, Financial instruments	(2,600)	(1,614)
Securities Lending and Reverse Repurchase Agreements, Net amount
Total, Gross amount of recognized liabilities	3,998	3,481
Total, Gross amounts offset	(55)
Total, Net amount of liabilities	3,943	3,481
Total, Financial instruments	(2,600)	(1,614)
Total, Net amount	$ 1,343	$ 1,867