Stock Repurchase Program, Authorized, Increase Amount

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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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Face amount or stated value per share of common stock.

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

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Number of shares issued for each share of convertible preferred stock that is converted.

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

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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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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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Number of shares issued under share-based payment arrangement.

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Number of shares issued which are neither cancelled nor held in the treasury.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and are being held in treasury.

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The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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Shareholders’ Equity (Details) - USD ($)	3 Months Ended	6 Months Ended		75 Months Ended	126 Months Ended
Shareholders’ Equity (Details) - USD ($)	Mar. 31, 2015	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2011	Dec. 31, 2008
Class of Stock [Line Items]
Common stock, shares authorized (in shares)		195,000,000		195,000,000	195,000,000	195,000,000
Common stock, par value (in dollars per share)		$ 0.01		$ 0.01	$ 0.01	$ 0.01
Common stock, shares issued (in shares)		97,315,639		97,315,639	97,315,639	97,242,318
Common stock, shares, outstanding (in shares)		90,129,118		90,129,118	90,129,118	90,055,797
Preferred stock, shares authorized (in shares)		5,000,000		5,000,000	5,000,000	5,000,000
Preferred stock par value (in dollars per share)		$ 0.01		$ 0.01	$ 0.01	$ 0.01
Preferred shares issued (in shares)								160,000
Number of shares issued for each share of preferred stock (in shares)		100		100	100
Stock repurchase program, authorized amount	$ 130,000,000.0						$ 60,000,000.0
Stock repurchase program, authorized, increase amount	$ 70,000,000.0
Treasury stock, shares, acquired (in shares)				0	7,186,521
Treasury stock, value		$ 86,300,000		$ 86,300,000	$ 86,300,000	$ 86,300,000
Stock repurchase program, remaining authorized repurchase amount		$ 43,700,000		$ 43,700,000	$ 43,700,000
Preferred stock, Series A Convertible [Member]
Class of Stock [Line Items]
Preferred shares outstanding (in shares)		63,274		63,274	63,274	63,589
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)		63,589	67,323
Conversion of convertible preferred stock (in shares)		(315)	(1,284)
Issuance for share-based compensation plans (in shares)		0	0
Ending balance (in shares)		63,274	66,039	63,274	63,274
Treasury [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)		7,186,521	7,186,521
Conversion of convertible preferred stock (in shares)		0	0
Issuance for share-based compensation plans (in shares)		0	0
Ending balance (in shares)		7,186,521	7,186,521	7,186,521	7,186,521
Common stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)		90,055,797	89,185,661
Conversion of convertible preferred stock (in shares)		31,465	128,389
Issuance for share-based compensation plans (in shares)		41,856	170,784
Ending balance (in shares)		90,129,118	89,484,834	90,129,118	90,129,118