Common Stock, Voting Rights, Votes Per Share Owned

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- Definition

The maximum aggregate stock voting power held by a class of common stock.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Face amount or stated value per share of common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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- Definition

Amount of expense for employee benefit and equity-based compensation.

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No definition available.

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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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

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Number of new stock issued during the period.

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Capital Stock and Equity-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	100,000,000.0		100,000,000.0		100,000,000
Preferred stock, par value (usd per share)	$ 0.01		$ 0.01		$ 0.01
Common stock, shares authorized (in shares)	585,000,000		585,000,000		585,000,000
Preferred stock, shares issued (in shares)	0		0		0
Preferred Stock, Shares Outstanding	0		0		0
Restricted Stock [Member]
Class of Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period			56,000	78,300
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value			$ 0.8	$ 1.3
General and Administrative Expense [Member] \| Restricted Stock [Member]
Class of Stock [Line Items]
Employee Benefits and Share-based Compensation	$ 0.5	$ 0.4	$ 1.4	$ 1.3
Common Class A [Member]
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	485,000,000.0		485,000,000.0		485,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01		$ 0.01		$ 0.01
Common Stock, Voting Rights, Votes Per Share Owned			$ 1
Common stock, shares issued (in shares)	29,200,000		29,200,000		29,100,000
Common Stock, Shares, Outstanding	29,200,000		29,200,000		29,100,000
Common Class A [Member] \| Restricted Stock Units
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues			35,700	44,800
Common Class B [Member]
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	100,000,000.0		100,000,000.0		100,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01		$ 0.01		$ 0.01
Common Stock, Voting Rights, Votes Per Share Owned			$ 5
Maximum percentage of voting power			49.00%
Common stock, shares issued (in shares)	4,600,000		4,600,000		4,600,000
Common Stock, Shares, Outstanding	4,600,000		4,600,000		4,600,000