Earnings per Share - Summary of Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - USD ($) $ 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]
Total	6,085,742	5,461,704	4,680,651	5,461,704
Fair value of warrants		$ 1,525		$ 3,109
Stock Options, SARs, and RSUs to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total	6,085,742	5,051,465	4,680,651	5,051,465
Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total		410,239		410,239

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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