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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Share-based compensation actual payout as a percentage of the target.

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Share-based compensation potential payout as a percentage of the target.

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Equity-Based Compensation - PSUs (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Feb. 28, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Performance Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years	3 years
Potential payout (as a percent)		100.00%
Shares issued under the plan	435,000
Unvested, Units, beginning of year		999,000
Granted, Units		336,000
Vested, Units	(659,000)	(353,000)
Forfeited, Units		(14,000)
Unvested, Units, end of year		968,000	999,000
Unvested, Weighted Average Per Share Fair Value, beginning of year		$ 120.95
Granted, Weighted Average Per Share Fair Value		122.59
Vested, Weighted Average Per Share Fair Value		98.45
Forfeited, Weighted Average Per Share Fair Value		130.49
Unvested, Weighted Average Per Share Fair Value, end of year		$ 129.60	$ 120.95
Total fair market value of vested awards		$ 74	$ 89	$ 84
Total Shareholder Return Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Actual payout (as a percent)			172.84%
Cash Flow Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Actual payout (as a percent)			200.00%
Deferred Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based awards outstanding (in shares)		201,000
Minimum [Member] \| Performance Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential payout (as a percent)		0.00%
Maximum [Member] \| Performance Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential payout (as a percent)		200.00%