Goodwill (Goodwill) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2013
Goodwill Rollforward and by Segment
Goodwill	$ 111us-gaap_GoodwillGross	$ 111us-gaap_GoodwillGross	$ 111us-gaap_GoodwillGross
Accumulated impairment	0	(10)	(10)
Goodwill total	111us-gaap_Goodwill	101us-gaap_Goodwill	101us-gaap_Goodwill
Impairments	(10)us-gaap_GoodwillImpairmentLoss
Goodwill	111us-gaap_GoodwillGross	111us-gaap_GoodwillGross	111us-gaap_GoodwillGross
Accumulated impairment	(10)	(10)	(10)
Goodwill total	101us-gaap_Goodwill	101us-gaap_Goodwill	101us-gaap_Goodwill
Retail
Goodwill Rollforward and by Segment
Goodwill	37	37	37
Accumulated impairment	0	(10)	(10)
Goodwill total	37	27	27
Impairments	(10)
Goodwill	37	37	37
Accumulated impairment	(10)	(10)	(10)
Goodwill total	27	27	27
Group, Voluntary & Worksite Benefits
Goodwill Rollforward and by Segment
Goodwill	68	68	68
Accumulated impairment	0	0	0
Goodwill total	68	68	68
Impairments	0
Goodwill	68	68	68
Accumulated impairment	0	0	0
Goodwill total	68	68	68
Corporate Benefit Funding
Goodwill Rollforward and by Segment
Goodwill	2	2	2
Accumulated impairment	0	0	0
Goodwill total	2	2	2
Impairments	0
Goodwill	2	2	2
Accumulated impairment	0	0	0
Goodwill total	2	2	2
Corporate & Other
Goodwill Rollforward and by Segment
Goodwill	4	4	4
Accumulated impairment	0	0	0
Goodwill total	4	4	4
Impairments	0
Goodwill	4	4	4
Accumulated impairment	0	0	0
Goodwill total	$ 4	$ 4	$ 4

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

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-Section 50

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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

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