Stock Compensation Plans - Stock-Based Compensation Expense Included in Consolidated Statement of Income and Comprehensive Income (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 62	$ 40	$ 38
Less tax benefit	(13)	(8)	(7)
Total stock-based compensation, net of tax	49	32	31
Equity-based awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	54	36	34
Liability-based awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 8	$ 4	$ 4

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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