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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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Shareholders’ Equity (Details) - USD ($)	3 Months Ended	6 Months Ended		63 Months Ended	114 Months Ended
Shareholders’ Equity (Details) - USD ($)	Mar. 31, 2015	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	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)		96,671,355		96,671,355	96,671,355	96,372,182
Common stock, shares, outstanding (in shares)		89,484,834		89,484,834	89,484,834	89,185,661
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, acquired, cost method					$ 86,300,000
Stock repurchase program, remaining authorized repurchase amount		$ 43,700,000		$ 43,700,000	$ 43,700,000
Series A Convertible Preferred Stock [Member]
Class of Stock [Line Items]
Preferred shares outstanding (in shares)		66,039		66,039	66,039	67,323
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)		67,323	71,967
Conversion of convertible preferred stock (in shares)		(1,284)	(3,392)
Issuance for stock compensation plans (in shares)		0	0
Ending balance (in shares)		66,039	68,575	66,039	66,039
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 stock 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)		89,185,661	88,103,440
Conversion of convertible preferred stock (in shares)		128,389	339,166
Issuance for stock compensation plans (in shares)		170,784	451,161
Ending balance (in shares)		89,484,834	88,893,767	89,484,834	89,484,834