Stock-Based Payments - Weighted-Average Assumptions to Estimate Fair Value of Stock Options (Details) - $ / shares |
12 Months Ended | ||
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Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Stock Option | |||
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||
| Weighted-average grant date fair value of options granted (in dollars per share) | $ 5.30 | $ 5.05 | $ 7.80 |
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- Definition 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. No definition available.
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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