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Goodwill and Other Intangibles - Changes in the carrying value of goodwill (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2015 | Dec. 31, 2015 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2014
Changes in the carrying value of goodwill by reporting segment |  |  |  |  |
Goodwill, Beginning balance | $ 199 | $ 199 | $ 199 | $ 199 | $ 201
Goodwill, Sale of subsidiary | (2) | (2) |  |  |
Goodwill, Ending balance | 199 | 199 |  |  |
Property and Casualty |  |  |  |  |
Changes in the carrying value of goodwill by reporting segment |  |  |  |  |
Goodwill, Beginning balance | 168 | 168 | 168 | 168 | 168
Goodwill, Sale of subsidiary |  | 0 |  |  |
Goodwill, Ending balance | 168 | 168 |  |  |
Annuity |  |  |  |  |
Changes in the carrying value of goodwill by reporting segment |  |  |  |  |
Goodwill, Beginning balance | 31 | 31 | $ 31 | $ 31 | $ 33
Goodwill, Sale of subsidiary |  | (2) |  |  |
Goodwill, Ending balance | $ 31 | $ 31 |  |  |

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -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 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of divestiture 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 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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- Details
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- Details
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