Fair Value Hierarchy - Investments Accounted for at Fair Value (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	$ 78,201	$ 83,427
Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in funds at NAV	2,941	3,469
Investment at fair value	75,260	79,958
Level 1 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	50,939	51,175
Level 2 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	7,379	14,881
Level 3 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	16,942	13,902
U.S. | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	47,055	46,322
U.S. | Level 1 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	47,055	46,322
U.S. | Level 2 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	0	0
U.S. | Level 3 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	0	0
Non-U.S. | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	2,235	2,612
Non-U.S. | Level 1 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	2,169	2,612
Non-U.S. | Level 2 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	66	0
Non-U.S. | Level 3 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	0	0
Corporate debt securities | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	10,098	9,793
Corporate debt securities | Level 1 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	145	65
Corporate debt securities | Level 2 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	2,950	5,201
Corporate debt securities | Level 3 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	7,003	4,527
Securities backed by real estate | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	1,003	2,280
Securities backed by real estate | Level 1 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	0	0
Securities backed by real estate | Level 2 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	176	1,202
Securities backed by real estate | Level 3 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	827	1,078
Money market instruments | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	1,005	1,396
Money market instruments | Level 1 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	48	41
Money market instruments | Level 2 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	957	1,355
Money market instruments | Level 3 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	0	0
Other debt obligations | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	259	417
Other debt obligations | Level 1 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	0	0
Other debt obligations | Level 2 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	3	35
Other debt obligations | Level 3 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	256	382
Equity securities | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	13,605	17,138
Equity securities | Level 1 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	1,522	2,135
Equity securities | Level 2 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	3,227	7,088
Equity securities | Level 3 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment at fair value	$ 8,856	$ 7,915