Derivative Instruments - Summary of Gross Fair Values of Individual Derivative Instruments (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 26	$ 28
Derivative Asset, Fair Value, Amount Offset Against Collateral	0	0
Net Amounts of Assets Presented in the Consolidated Balance Sheet, Derivative Assets	26	27
Net Amounts of Liabilities Presented in the Consolidated Balance Sheet, Derivative Liabilities	35	38
Derivative Liabilities Gross Amount Of Collateral Cash And Securities Pledged Not Offset		38
Fair value of derivative liabilities	35
Net Amount, Derivative Assets	26	27
Net Amount, Derivative Liabilities	0	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	0	0
Derivative Liability, Fair Value, Gross Liability	35	38
Derivative Liability, Fair Value, Amount Offset Against Collateral	0	0
Variable Interest Entity [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	226	239
Derivative Asset, Fair Value, Amount Offset Against Collateral	0	0
Net Amounts of Assets Presented in the Consolidated Balance Sheet, Derivative Assets	226	239
Net Amounts of Liabilities Presented in the Consolidated Balance Sheet, Derivative Liabilities	1,197	1,048
Derivative Liabilities Gross Amount Of Collateral Cash And Securities Pledged Not Offset		0
Fair value of derivative liabilities	0
Net Amount, Derivative Assets	0	239
Net Amount, Derivative Liabilities	1,197	1,048
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	226	0
Derivative Liability, Fair Value, Gross Liability	1,197	1,048
Derivative Liability, Fair Value, Amount Offset Against Collateral	0	0
Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	25	27
Derivative Asset, Fair Value, Amount Offset Against Collateral	0	0
Net Amounts of Assets Presented in the Consolidated Balance Sheet, Derivative Assets	25	27
Net Amounts of Liabilities Presented in the Consolidated Balance Sheet, Derivative Liabilities	35	38
Fair value of derivative liabilities	35	38
Net Amount, Derivative Assets	25	27
Net Amount, Derivative Liabilities	0	0
Derivative Asset, Fair Value, Amount Not Offset Against Collateral		0
Derivative Liability, Fair Value, Gross Liability	35	38
Derivative Liability, Fair Value, Amount Offset Against Collateral	0	0
Interest Rate Swaps [Member] | Variable Interest Entity [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	190	190
Derivative Asset, Fair Value, Amount Offset Against Collateral	0	0
Net Amounts of Assets Presented in the Consolidated Balance Sheet, Derivative Assets	190	190
Net Amounts of Liabilities Presented in the Consolidated Balance Sheet, Derivative Liabilities	1,197	1,048
Net Amount, Derivative Assets	0	190
Net Amount, Derivative Liabilities	1,197	1,048
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	190
Derivative Liability, Fair Value, Gross Liability	1,197	1,048
Interest Rate Swaps [Member] | Variable Interest Entity [Member] | Level 3 [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Currency Swaps [Member] | Variable Interest Entity [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	36	49
Derivative Asset, Fair Value, Amount Offset Against Collateral	0
Net Amounts of Assets Presented in the Consolidated Balance Sheet, Derivative Assets	36	49
Net Amount, Derivative Assets	0	49
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	36	0
Warrant [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	1	1
Net Amounts of Assets Presented in the Consolidated Balance Sheet, Derivative Assets	1	1
Net Amount, Derivative Assets	$ 1	$ 1