Earnings Per Share - Computation of Basic and Diluted Earnings Per Share for Continuing Operations (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Numerator:
Income from continuing operations	$ 50,216	$ 36,862
Basic
Weighted average common shares outstanding (in shares)	53,366	54,571
Diluted
Stock options (in shares)	776	993
Restricted stock awards (in shares)	257	296
Contingent shares (in shares)	37	85
Diluted weighted average common shares outstanding (in shares)	54,436	55,945
Basic earnings per share from continuing operations (in dollars per share)	$ 0.94	$ 0.68
Diluted earnings per share from continuing operations (in dollars per share)	$ 0.92	$ 0.66
Share-based payment arrangement
Dilutive Securities Included And Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Share based awards excluded from the calculation of diluted earnings per share (in shares)	1	33
Performance shares
Dilutive Securities Included And Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Share based awards excluded from the calculation of diluted earnings per share (in shares)	447	332

Dilutive securities included and antidilutive securities excluded from computation of earnings per share.

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Incremental common shares attributable to restricted stock awards.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Amount after tax of income (loss) from continuing operations attributable to the parent.

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The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of contingently issuable shares. Contingently issuable shares are those shares that are issuable for little or no cash contingent on certain conditions being met.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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