Fair Value Disclosures - Investments in Certain Entities Calculate Net Asset Value per Share (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments	$ 725	$ 789
Fair Value Measured at NAV per share [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Fair Value	2,977	2,030
Hedge Funds/Funds of Hedge Funds/Other Member \| Consolidated Variable Interest Entities Member
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments	$ 64
Redemption Frequency (Quarterly)	83.00%
Redemption Frequency (Not Redeemable)	17.00%
Hedge Funds/Funds of Hedge Funds/Other Member \| Consolidated Variable Interest Entities Member \| Fair Value Measured at NAV per share [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Fair Value	$ 168
Private Equity Funds [Member] \| Consolidated Variable Interest Entities Member
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments	37	37
Private Equity Funds [Member] \| Consolidated Variable Interest Entities Member \| Fair Value Measured at NAV per share [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Fair Value	145	183
Real Assets Funds Member
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments	272	398
Real Assets Funds Member \| Consolidated Variable Interest Entities Member
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments	62	94
Real Assets Funds Member \| Consolidated Variable Interest Entities Member \| Fair Value Measured at NAV per share [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Fair Value	$ 154	116
Other Funds [Member] \| Consolidated Variable Interest Entities Member
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments		$ 31
Redemption Notice Period, days	90 days	90 days
Other Funds [Member] \| Consolidated Variable Interest Entities Member \| Fair Value Measured at NAV per share [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Fair Value		$ 17
Equity Method Investments Member \| Hedge Funds/Funds of Hedge Funds/Other Member
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments	$ 134
Equity Method Investments Member \| Hedge Funds/Funds of Hedge Funds/Other [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments		$ 149
Redemption Frequency (Daily)	4.00%	23.00%
Redemption Frequency (Monthly)	4.00%	(23.00%)
Redemption Frequency (Quarterly)	8.00%	13.00%
Redemption Frequency (Not Redeemable)	88.00%	64.00%
Equity Method Investments Member \| Hedge Funds/Funds of Hedge Funds/Other [Member] \| Fair Value Measured at NAV per share [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Fair Value	$ 588	$ 525
Equity Method Investments Member \| Hedge Funds/Funds of Hedge Funds/Other [Member] \| Minimum [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Redemption Notice Period, days	1 day	1 day
Equity Method Investments Member \| Hedge Funds/Funds of Hedge Funds/Other [Member] \| Maximum [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Redemption Notice Period, days	90 days	90 days
Equity Method Investments Member \| Private Equity Funds [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments	$ 218	$ 174
Equity Method Investments Member \| Private Equity Funds [Member] \| Fair Value Measured at NAV per share [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Fair Value	1,264	885
Equity Method Investments Member \| Real Assets Funds Member
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments	$ 210	$ 304
Redemption Frequency (Quarterly)	10.00%	17.00%
Redemption Frequency (Not Redeemable)	90.00%	83.00%
Redemption Notice Period, days	60 days	60 days
Equity Method Investments Member \| Real Assets Funds Member \| Fair Value Measured at NAV per share [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Fair Value	$ 417	$ 304
Equity Method Investments Member \| Investments Related To Deferred Cash Compensation Plans Member
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Total Unfunded Commitments	0
Equity Method Investments Member \| Investments Related To Deferred Cash Compensation Plans Member \| Fair Value Measured at NAV per share [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Fair Value	$ 241
Equity Method Investments Member \| Deferred Cash Compensation Plan Equity Method Investments [Member] \| Minimum [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Redemption Notice Period, days	1 day
Equity Method Investments Member \| Deferred Cash Compensation Plan Equity Method Investments [Member] \| Maximum [Member]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share Line Items
Redemption Notice Period, days	90 days

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Fair value measured recurring basis using net asset per share value redemption frequency (monthly).

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Fair value measured recurring basis using net asset per share value redemption frequency not redeemable.

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Fair value measured recurring basis using net asset per share value redemption frequency (quarterly).

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Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 54B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482134/820-10-35-54B

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-6A

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Notice period the entity is required to deliver before it can redeem an investment calculated using net asset value per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investments calculated by per unit, per membership interest, other equity or ownership interest and alternative investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-6A

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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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The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-6A

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