Closed Block (Policyholder Dividend Obligation) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Closed block policyholder dividend obligation
Balance at January 1,	$ 1,771	$ 3,828	$ 2,919
Change in unrealized investment and derivative gains (losses)	1,384	(2,057)	909
Balance at December 31,	$ 3,155	$ 1,771	$ 3,828

The liability as of the balance sheet date for the excess of the cumulative actual closed block earnings over the cumulative expected (actuarially determined) closed block earnings (each) for the period from the actuarial calculation date to the date of measurement. The excess will result in future dividends to closed block policyholders, unless offset by less favorable than expected future performance of the closed block. The policyholder dividend obligation, which may not have a negative balance, recognizes that a portion of earnings in certain cases will not inure to the stockholders of the insurance entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 805

-Section 55

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=34726331&loc=d3e31071-158570

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 805

-Section 50

-Paragraph 3

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=6487222&loc=d3e30806-158569

Name:	us-gaap_ClosedBlockLiabilitiesPolicyholderDividendObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant