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Segments of Operations - Narrative (Details) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 USD ($) | Mar. 31, 2017 USD ($) | Jun. 30, 2018 segment
Segment Reporting Information [Line Items] |  |  |
Number of segments | segment |  |  | 3
Property and Casualty Insurance | Real Estate Investment |  |  |
Segment Reporting Information [Line Items] |  |  |
Pretax income from the sale of real estate properties |  | $ 13 |
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Write off of Deferred Debt Issuance Cost | $ 7 |  |

X
- Definition This element represents the amount of gain (loss) on sale of properties during the reporting period gross of the applicable income taxes realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 974 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-15.(a)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6875705&loc=d3e641549-123027 + Details
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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
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- Definition Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Details
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- Details
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