Charges and Credits - Summary of Charges and Credits (Detail) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2022
Charges And Credits [Line Items]
Charges and credits, Pretax Credit				$ 285,000,000
Charges and credits, Tax Expense				19,000,000
Charges and credits, Net	$ 0			$ 266,000,000
Interest And Other | Gain On Sale Of Liberty Shares
Charges And Credits [Line Items]
Charges and credits, Pretax Credit		$ 216,000,000	$ 26,000,000
Charges and credits, Tax Expense		13,000,000	4,000,000
Charges and credits, Net		203,000,000	$ 22,000,000
Interest And Other | Gain On Sale Of Real Estate
Charges And Credits [Line Items]
Charges and credits, Pretax Credit		43,000,000
Charges and credits, Tax Expense		2,000,000
Charges and credits, Net		$ 41,000,000