XML 101 R74.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Investments - Realized capital gains and losses by asset type (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Realized capital gains and losses by asset type |  |  |
Realized capital gains and losses | $ 445 | $ (90) | $ 30
Fixed income securities |  |  |
Realized capital gains and losses by asset type |  |  |
Realized capital gains and losses | 94 | (91) | 212
Equity securities |  |  |
Realized capital gains and losses by asset type |  |  |
Realized capital gains and losses | 255 | 23 | (50)
Mortgage loans |  |  |
Realized capital gains and losses by asset type |  |  |
Realized capital gains and losses | 1 | 0 | 6
Limited partnership interests |  |  |
Realized capital gains and losses by asset type |  |  |
Realized capital gains and losses | 132 | (21) | (93)
Derivatives |  |  |
Realized capital gains and losses by asset type |  |  |
Realized capital gains and losses | (46) | 3 | (21)
Other |  |  |
Realized capital gains and losses by asset type |  |  |
Realized capital gains and losses | $ 9 | $ (4) | $ (24)

X
- Definition The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.3(a)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 325 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=75031664&loc=d3e22529-158502 + Details
Name: | us-gaap_RealizedInvestmentGainsLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ScheduleOfGainLossOnInvestmentsIncludingMarketableSecuritiesAndInvestmentsHeldAtCostIncomeStatementReportedAmountsSummaryLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_FixedIncomeSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_MortgagesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_PartnershipInterestMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_DerivativeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_OtherThanSecuritiesInvestmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |