Stockholders' Equity - Restricted Stock Units and Restricted Stock Awards - Unrecognized Share-based Compensation Expense (Details) - Unvested restricted stock units/awards $ in Millions  | 
6 Months Ended | 
|---|---|
| 
 Jun. 30, 2021  
USD ($)  
shares 
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| Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized [Abstract] | |
| Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options | $ | $ 0.2 | 
| Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition | 10 months 24 days | 
| Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested Upon Performance | shares | 487,586 | 
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding which are performance-based and vest upon achievement of certain corporate milestones as of the balance sheet date. No definition available. 
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- References No definition available. 
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Details 
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