Stock-Based Compensation Plans - Status and Activity of Nonvested Stock Awards (Details) - $ / shares	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Nonvested Stock Awards [Roll Forward]
Nonvested, beginning of period (in shares)	5,101,025
Granted (in shares)	3,361,265
Vested (in shares)	(1,517,986)
Performance adjustment factor (in shares)	(280,713)
Forfeited or expired (in shares)	(249,276)
Nonvested, end of period (in shares)	6,414,315	5,101,025
Weighted- Average Grant-Date Fair Value
Beginning of period (in USD per share)	$ 16.85
Granted (in USD per share)	20.24
Vested (in USD per share)	19.01
Performance adjustment factor (in USD per share)	47.83
Forfeited or expired (in USD per share)	14.43
End of period (in USD per share)	$ 16.85	$ 16.85
Percentage of original grants of awards to targeted amounts	100.00%
Restricted Stock Units
Nonvested Stock Awards [Roll Forward]
Nonvested, beginning of period (in shares)	3,515,725
Granted (in shares)	1,891,481	2,640,690	1,005,500
Vested (in shares)	(1,517,986)
Performance adjustment factor (in shares)	0
Forfeited or expired (in shares)	(189,531)
Nonvested, end of period (in shares)	3,699,689	3,515,725
TSR Performance Awards
Nonvested Stock Awards [Roll Forward]
Nonvested, beginning of period (in shares)	918,564
Granted (in shares)	306,930	671,390	210,520
Vested (in shares)	0
Performance adjustment factor (in shares)	(69,483)
Forfeited or expired (in shares)	(34,308)
Nonvested, end of period (in shares)	1,121,703	918,564
ROCE Performance Awards
Nonvested Stock Awards [Roll Forward]
Nonvested, beginning of period (in shares)	666,736
Granted (in shares)	485,900
Vested (in shares)	0
Performance adjustment factor (in shares)	(211,230)
Forfeited or expired (in shares)	(25,437)
Nonvested, end of period (in shares)	915,969	666,736
Performance-Based Restricted Stock Units
Nonvested Stock Awards [Roll Forward]
Nonvested, beginning of period (in shares)	0
Granted (in shares)	676,954	0	0
Vested (in shares)	0
Performance adjustment factor (in shares)	0
Forfeited or expired (in shares)	0
Nonvested, end of period (in shares)	676,954	0

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Share -based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Market and/or Performance Conditions, Adjustments in Period.

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Share -based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Market and/or Performance Conditions, percentage adjustments in the period.

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Share based Compensation Arrangement by Share based Payment Award, Equity Instruments Other than Options, Weighted Average Grant Date Fair Value [Abstract]

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