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Stock-Based Compensation Plans - Additional Information (Details) $ / shares in Units, $ in Millions		1 Months Ended					12 Months Ended
	Jun. 05, 2020 USD ($)	Oct. 31, 2021 shares	Mar. 31, 2021 shares	Dec. 31, 2020 shares	Dec. 31, 2019 shares	Dec. 31, 2018 USD ($) shares	Sep. 30, 2022 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2017 employee shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share awards vesting period							2 years
Number of additional employees to participate in plan \| employee										2
Modification of stock-based compensation plan \| $									$ 769
Weighted-average grant date intrinsic value of share awards (in dollars per share) \| $ / shares									$ 23.82
Unrecognized compensation costs \| $							$ 1	$ 4	$ 14
Total compensation of unvested awards expected to be recognized, weighted average period							1 year
Non-cash compensation expense \| $							$ 39	$ 45	$ 608
IPO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Modification of stock-based compensation plan \| $	$ 769
Proceeds from issuance initial public offering \| $	$ 57
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of deferred equity units (in dollars per share) \| $ / shares							$ 38.50	$ 32.29
Unrecognized compensation costs \| $							$ 31
Total compensation of unvested awards expected to be recognized, weighted average period							2 years 8 months 12 days
Granted (in dollars per share) \| $ / shares							$ 44.38	$ 32.23
Awards vested in period, fair value \| $							$ 18	$ 0
Senior Management Free Cash Flow Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized (in shares)										39,255,429.54
Deferred equity unit share (in shares)					314,631.58	314,631.58				19,612,714.77
Senior Management Free Cash Flow Plan \| LLC
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized (in shares)										3,896,654
Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under Omnibus Incentive Plan (in shares)							463,826	36,206	28,361
Shares issued in period (in shares)				4,321,259
Common Class A \| Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares available for grant (in shares)							31,169,099
Share awards vesting period							10 years
Shares held in employee stock option plan, allocated (in shares)							528,393
Common stock available for issuance (in shares)							30,640,706
Common Class A \| Omnibus Incentive Plan \| IPO
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized (in shares)							1,000,000
Common Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exchange of Class B shares for Class A shares (in shares)		510,165	968,920	18,265,183
Deferred Equity Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date intrinsic value of share awards (in dollars per share) \| $ / shares							$ 0	$ 0
Fair value of deferred equity units (in dollars per share) \| $ / shares									$ 27.01
Deferred Equity Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share awards vesting period							1 year
Deferred Equity Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share awards vesting period							7 years
Fractional Shares \| Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash paid to settle awards \| $						$ 2
Awards settled (in shares)						8,359,629.35
Matching Equity Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash paid to settle awards \| $						$ 1
Weighted-average grant date intrinsic value of share awards (in dollars per share) \| $ / shares							$ 0	$ 0
Matching Equity Units \| Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash paid to settle awards \| $						$ 58
Awards settled (in shares)						217,312.53
Common Stock \| Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under Omnibus Incentive Plan (in shares)							187,261	36,206	28,361
Vesting of restricted stock units, net of shares withheld for employee taxes (in shares)							276,565
Exchange of Class B shares for Class A shares (in shares)							14,320,547	19,234,103
Common Stock \| Common Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exchange of Class B shares for Class A shares (in shares)							14,320,547	19,234,106