Earnings per Share - Summary of Net (Loss) Earning Attributable to Shareholders and Reconciliation of Basic and Diluted Shares (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net income (loss) attributable to shareholders	$ 48,318	$ (65,840)	$ 11,897	$ (9,438)
Weighted average common shares outstanding – Basic (in shares)	44,861	44,166	44,664	43,720
Dilutive impact of share-based compensation awards (in shares)	418	0	670	0
Weighted average common shares outstanding – Diluted (in shares)	45,279	44,166	45,334	43,720
Antidilutive securities excluded from computation of earnings (in shares)	700	800	900	700
Convertible Debt Securities
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings (in shares)	1,600	1,600	1,600	1,600

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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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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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

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-Publisher FASB
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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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Net Income (Loss) Attributable to Parent, After Accretion of Non-controlling Interest

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