Leases - Balance Sheet Information Related to Operating & Finance Leases (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Operating lease right-of-use assets — net	$ 352	$ 426
Finance lease right-of-use assets — net	$ 144	$ 168
Operating Lease obligations:
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Current portion of operating and finance lease obligations	Current portion of operating and finance lease obligations
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Current portion of operating and finance lease obligations	Current portion of operating and finance lease obligations
Current operating lease obligations	$ 70	$ 63
Long-term operating lease obligations	394	478
Total lease obligations	464	541
Finance Lease Obligations:
Current finance lease obligations	19	18
Long-term finance lease obligations	200	220
Total lease obligations	219	238
Finance lease ROU assets cost	212	212
Finance lease ROU assets accumulated amortization	$ 68	$ 44