Related Party Transactions (Reinsurance Transactions - Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Reinsurance Disclosures [Abstract]
Embedded Derivative, Fair Value of Embedded Derivative Asset	$ 1,766		$ 1,766		$ 3,537
Net derivatives gains (losses)	(16)	91	165	270
Embedded Derivative, Fair Value of Embedded Derivative Liability	(606)		(606)		1,261
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	138	(193)	900	551
Affiliated Entity [Member] \| Ceded Guaranteed Minimum Benefit [Member]
Reinsurance Disclosures [Abstract]
Embedded Derivative, Fair Value of Embedded Derivative Asset	1,800		1,800		3,600
Net derivatives gains (losses)	(607)	(344)	(2,000)	(357)
Affiliated Entity [Member] \| Funds Withheld On Ceded Reinsurance [Member]
Reinsurance Disclosures [Abstract]
Net derivatives gains (losses)	48	(37)	477	(186)
Coinsurance Funds Withheld Basis, Percent	90.00%		90.00%
Embedded Derivative, Fair Value of Embedded Derivative Liability	85		85		546
Affiliated Entity [Member] \| Certain term and universal life policies issued in 2012 by MLI-USA [Member]
Reinsurance Disclosures [Abstract]
Coinsurance Funds Withheld Basis, Percent	90.00%		90.00%
Embedded Derivative, Fair Value of Embedded Derivative Liability	(10)		(10)		6
Reinsurance recoverables	339		339		407
Funds Held under Reinsurance Agreements, Liability	213		213		438
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest	$ 6		$ 36

Percentage of business ceded on a coinsurance funds withheld basis.

No definition available.

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- Definition

Amount of reinsurance recoverable balances in both asset and liability accounts that have been ceded.

+ References

No definition available.

+ Details

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- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as an asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

+ Details

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Period Type:	instant

- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

+ References

+ Details

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Period Type:	instant

- Definition

Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

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- Definition

Amount of funds held as security for payments to be received under reinsurance contracts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.13(c))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph c

-Article 7

+ Details

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- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 5

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