Condensed Consolidated Balance Sheets (Parenthetical) - shares	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020
Statement Of Financial Position [Abstract]
Common stock, shares outstanding	111,476,496	110,781,613	94,602,386
Common stock, shares issued	122,790,983	122,061,711	121,819,456
Treasury stock, shares	11,314,487	11,280,098	27,217,070

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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-Publisher FASB
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-Section S99
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-Subparagraph (SX 210.5-02(29))
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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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-Publisher FASB
-Name Accounting Standards Codification
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