The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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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.

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No definition available.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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The amount of loss reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Derivative Instruments - Derivatives - Cash Flow Hedges (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months			$ 24,000,000
AOCI Attributable to Parent [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Loss on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring	$ 0	$ 0	0	$ 0
Cash Flow Hedging \| Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	0	(2,000,000)	(15,000,000)	8,000,000
Gain (Loss) on Cash Flow Hedge Ineffectiveness, Net	0	0	0	0
Cash Flow Hedging \| Designated as Hedging Instrument \| Reclassification out of Accumulated Other Comprehensive Income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	7,000,000	8,000,000	25,000,000	32,000,000
Cash Flow Hedging \| Designated as Hedging Instrument \| Interest rate swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)		2,000,000	(16,000,000)	16,000,000
Cash Flow Hedging \| Designated as Hedging Instrument \| Interest rate swaps \| Reclassification out of Accumulated Other Comprehensive Income \| Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent \| Net realized capital gains
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	0	0	1,000,000	5,000,000
Cash Flow Hedging \| Designated as Hedging Instrument \| Interest rate swaps \| Reclassification out of Accumulated Other Comprehensive Income \| Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent \| Net investment income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	$ 7,000,000	8,000,000	24,000,000	27,000,000
Cash Flow Hedging \| Designated as Hedging Instrument \| Foreign currency swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Recognized in OCI on Derivative (Effective Portion)		$ (4,000,000)	$ 1,000,000	$ (8,000,000)