Supplemental Cash Flow Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Supplemental Cash Flow Information [Abstract]
Non-cash modifications of certain mortgage loans, fixed income securities, limited partnership interests and other investments, as well as mergers completed with equity securities	$ 12us-gaap_TransferOfInvestments	$ 49us-gaap_TransferOfInvestments
Non-cash financing activities related to the issuance of shares for vested restricted stock units	68	39
Net change in proceeds managed
Net change in short-term investments	27	(155)
Operating cash flow provided (used)	27	(155)
Net change in cash	0	(1)
Net change in proceeds managed	27	(156)
Net change in liabilities
Liabilities for collateral, beginning of period	(782)	(624)
Liabilities for collateral, end of period	(755)	(780)
Operating cash flow (used) provided	$ 27	$ (156)

The net operating cash flow provided by (used in) the net change in liabilities for collateral.

No definition available.

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- Definition

The net operating cash flow provided or used related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

+ References

No definition available.

+ Details

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- Definition

The net change in cash from the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

+ References

No definition available.

+ Details

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- Definition

The net change in the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

+ References

No definition available.

+ Details

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- Definition

The net change in short-term investments from the proceeds managed related to collateral received in conjunction with the entity's securities lending and over-the-counter derivatives.

+ References

No definition available.

+ Details

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- Definition

The liability to return cash and securities received as collateral in conjunction with securities lending and over-the-counter derivatives.

+ References

No definition available.

+ Details

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- Definition

Value of stock issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29-31)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30, 31

-Article 5

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- Definition

Value of investments transferred from the entity's investments in noncash transactions.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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