Derivative Financial Instruments - FGL's Exposure to Credit Loss on Call Options Held (Detail) $ in Millions	Sep. 30, 2020 USD ($)
Derivatives, Fair Value [Line Items]
Fair Value	$ 404
Call options
Derivatives, Fair Value [Line Items]
Fair Value	381
Not Designated as Hedging Instrument \| Call options
Derivatives, Fair Value [Line Items]
Notional Amount	15,437
Fair Value	381
Collateral	335
Net Credit Risk	47
Not Designated as Hedging Instrument \| Call options \| Merrill Lynch
Derivatives, Fair Value [Line Items]
Notional Amount	2,580
Fair Value	39
Collateral	0
Net Credit Risk	39
Not Designated as Hedging Instrument \| Call options \| Deutsche Bank
Derivatives, Fair Value [Line Items]
Notional Amount	20
Fair Value	1
Collateral	1
Net Credit Risk	0
Not Designated as Hedging Instrument \| Call options \| Morgan Stanley
Derivatives, Fair Value [Line Items]
Notional Amount	1,557
Fair Value	17
Collateral	18
Net Credit Risk	0
Not Designated as Hedging Instrument \| Call options \| Barclay's Bank
Derivatives, Fair Value [Line Items]
Notional Amount	4,563
Fair Value	152
Collateral	149
Net Credit Risk	3
Not Designated as Hedging Instrument \| Call options \| Canadian Imperial Bank of Commerce
Derivatives, Fair Value [Line Items]
Notional Amount	2,021
Fair Value	63
Collateral	61
Net Credit Risk	2
Not Designated as Hedging Instrument \| Call options \| Wells Fargo
Derivatives, Fair Value [Line Items]
Notional Amount	2,880
Fair Value	87
Collateral	85
Net Credit Risk	2
Not Designated as Hedging Instrument \| Call options \| Goldman Sachs
Derivatives, Fair Value [Line Items]
Notional Amount	736
Fair Value	6
Collateral	6
Net Credit Risk	0
Not Designated as Hedging Instrument \| Call options \| Credit Suisse
Derivatives, Fair Value [Line Items]
Notional Amount	648
Fair Value	7
Collateral	6
Net Credit Risk	1
Not Designated as Hedging Instrument \| Call options \| Truist
Derivatives, Fair Value [Line Items]
Notional Amount	432
Fair Value	9
Collateral	9
Net Credit Risk	$ 0

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after effects of master netting arrangements, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Nominal or face amount used to calculate payment on derivative.

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No definition available.

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