Commitments, Contingencies, And Guarantees (Narrative) (Detail) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Financial Instruments Owned and Pledged as Collateral [Line Items]
Derivative liability subject to a master netting agreement	$ 12	$ 30
Repurchase agreements	1,405	1,405
Purchase Commitment, Remaining Minimum Amount Committed	591
Carrying value of limited partnerships and partially-owned investment companies included in other investments	7,200	6,500
Funding commitments relating to limited partnerships and partially-owned investment companies	3,100	3,200
Unrecognized tax benefits	62
Operating Lease, Right-of-Use Asset	448	473
Operating Lease, Liability	$ 490	$ 517

Carrying value of limited partnerships and partially-owned investment companies included in other investments.

No definition available.

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- Definition

Fair value, after effects of master netting arrangements, of financial liability or 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 the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
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- 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.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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-Paragraph 1
-Subparagraph (b)
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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

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- Definition

Minimum amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations.

+ References

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- Definition

Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

+ References

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- Definition

Amount of unrecognized tax benefits.

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