Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

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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- Definition

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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Section 50
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-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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- Definition

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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No definition available.

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- Definition

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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- Definition

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

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- Definition

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 - Nonvested Restricted Stock Units (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Restricted Shares
Non-vested, beginning balance (in shares)	4,536,758
Granted (in shares)	876,296	2,314,542	1,218,613
Vested (in shares)	(1,398,118)
Forfeited (in shares)	(128,442)
Non-vested, ending balance (in shares)	3,886,494	4,536,758
Weighted- Average Grant- Date Fair Value
Non-vested, beginning balance (usd per share)	$ 29.54
Granted (usd per share	34.20	$ 32.89	$ 30.07
Vested (usd per share)	29.49
Forfeited (usd per share)	29.66
Non-vested, ending balance (usd per share)	$ 30.60	$ 29.54
U.K. Subsidiary Stock Plan
Restricted Shares
Granted (in shares)	86,000
Weighted- Average Grant- Date Fair Value
Award vesting period	5 years
Class B Common Stock Bonus
Restricted Shares
Granted (in shares)	375,796
Weighted- Average Grant- Date Fair Value
Vesting period, years	3 years
Class B Common Stock Key Employees
Restricted Shares
Granted (in shares)	414,500
Weighted- Average Grant- Date Fair Value
Vesting period, years	10 years