Derivative Instruments and Hedging Activities - Derivative Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Net Amount Presented in the Balance Sheet	$ 1	$ 2
Gross amounts not offset in the consolidated balance sheets financial instruments, derivative assets	1	2
Gross amounts not offset in the consolidated balance sheets cash collateral received, derivative assets	0	0
Net Amount	0	0
Interest rate contracts
Derivative [Line Items]
Net Amount Presented in the Balance Sheet	1	0
Gross amounts not offset in the consolidated balance sheets financial instruments, derivative assets	1
Gross amounts not offset in the consolidated balance sheets cash collateral received, derivative assets	0
Net Amount	0
Interest rate contracts
Derivative [Line Items]
Net Amount Presented in the Balance Sheet	$ 0	2
Gross amounts not offset in the consolidated balance sheets financial instruments, derivative assets		2
Gross amounts not offset in the consolidated balance sheets cash collateral received, derivative assets		0
Net Amount		$ 0

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
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Amount of obligation to return securities collateral under master netting arrangements that have not been offset against derivative assets.

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Fair value, after offset of derivative liability, 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, before offset against an obligation to return collateral under a master netting arrangement. 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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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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