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Derivatives - Narrative (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) swap | Mar. 31, 2017 USD ($) | Dec. 31, 2017 USD ($)
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Carrying value of collateral received to support purchased call options | $ 356,000,000 |  | $ 389,000,000
Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Number of interest rate swaps designated and qualifying as a cash flow hedges | swap | 11 |  |
Notional amount of derivative instrument outstanding | $ 1,680,000,000 |  | 1,580,000,000
Gain (loss) reclassified from AOCI into net investment income | 1,000,000 | $ 2,000,000 |
Gain (loss) on cash flow hedge ineffectiveness recorded in Net Earnings | 0 | $ 0 |
Collateral receivable supporting interest rate swaps | 107,000,000 |  | 70,000,000
Other assets | Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net derivatives, at fair value | 0 |  |
Other assets | Maximum | Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net derivatives, at fair value |  |  | 1,000,000
Other liabilities | Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Net derivatives, at fair value | (61,000,000) |  | $ (31,000,000)
New interest rate swaps entered into during the period | Cash Flow Hedges | Designated as Hedging Instrument | Interest rate swaps |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Notional amount of derivative instrument outstanding | $ 130,000,000 |  |
Number of interest rate swaps entered into during the period | swap | 1 |  |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624258-113959 + Details
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- Definition Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226016-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=d3e41678-113959 + Details
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13495-108611 + Details
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- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959 + Details
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- Definition The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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