Leases (Schedule of Maturity Analysis of Operating and Finance Lease Liabilities) (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Jan. 01, 2019
Operating Lease Liabilities, Payments Due [Abstract]
Maturity of operating lease liabilities, 2022	$ 3
Maturity of operating lease liabilities, 2023	2
Maturity of operating lease liabilities, 2024	2
Maturity of operating lease liabilities, 2025	1
Maturity of operating lease liabilities, 2026	1
Maturity of operating lease liabilities, after 2026	21
Maturity of operating lease liabilities, total undiscounted lease payments	30
Operating lease liabilities, present value adjustment	(11)
Present value of operating lease liabilities	19	$ 19
Finance Lease Liabilities, Payments, Due [Abstract]
Maturity of finance lease liabilities, 2022	5
Maturity of finance lease liabilities, 2023	4
Maturity of finance lease liabilities, 2024	3
Maturity of finance lease liabilities, 2025	1
Maturity of finance lease liabilities, 2026	1
Maturity of finance lease liabilities, after 2026	1
Maturity of finance lease liabilities, total undiscounted lease payments	15
Finance lease liabilities, present value adjustment	(1)
Present value of finance lease liabilities	$ 14