v3.20.2

Summary of Significant Accounting Policies and Other Information - Effect of Line Items on Consolidated Statement of Stockholders' Equity (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2019 | Sep. 30, 2019 | Dec. 31, 2019 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Jun. 30, 2019 | Dec. 31, 2018
Error Corrections and Prior Period Adjustments Restatement [Line Items] |  |  |  |  |  |  |  |
Equity balance | $ 20,277 | $ 20,277 | $ 28,497 | $ 9,036 | $ 10,355 |  | $ 14,391 | $ (18,578)
Additional Paid-in Capital |  |  |  |  |  |  |  |
Error Corrections and Prior Period Adjustments Restatement [Line Items] |  |  |  |  |  |  |  |
Stock-based compensation expense | (1,907) | (722) | (572) |  |  |  |  |
Equity balance | 156,580 | 156,580 | 156,727 | 157,138 | 157,052 | $ 156,891 | 158,530 | 119,724
Treasury Stock |  |  |  |  |  |  |  |
Error Corrections and Prior Period Adjustments Restatement [Line Items] |  |  |  |  |  |  |  |
Stock-based compensation expense | 2,080 | 1,823 | 1,820 |  |  |  |  |
Equity balance | (1,338) | (1,338) | (1,341) | $ (1,293) | (1,354) | (1,349) | (3,418) | (3,161)
Previously Reported | Additional Paid-in Capital |  |  |  |  |  |  |  |
Error Corrections and Prior Period Adjustments Restatement [Line Items] |  |  |  |  |  |  |  |
Stock-based compensation expense | (14) | 1,390 | 1,540 |  |  |  |  |
Equity balance | 165,380 | 165,380 | 165,527 |  | 165,852 | 165,691 | 165,437 | 126,412
Previously Reported | Treasury Stock |  |  |  |  |  |  |  |
Error Corrections and Prior Period Adjustments Restatement [Line Items] |  |  |  |  |  |  |  |
Stock-based compensation expense | 187 | (289) | (292) |  |  |  |  |
Equity balance | (10,138) | (10,138) | (10,141) |  | (10,154) | (10,149) | (10,325) | (9,849)
Adjustment | Additional Paid-in Capital | Adjustment |  |  |  |  |  |  |  |
Error Corrections and Prior Period Adjustments Restatement [Line Items] |  |  |  |  |  |  |  |
Stock-based compensation expense | (1,893) | (2,112) | (2,112) |  |  |  |  |
Equity balance | (8,800) | (8,800) | (8,800) |  | (8,800) | (8,800) | (6,907) | (6,688)
Adjustment | Treasury Stock | Adjustment |  |  |  |  |  |  |  |
Error Corrections and Prior Period Adjustments Restatement [Line Items] |  |  |  |  |  |  |  |
Stock-based compensation expense | 1,893 | 2,112 | 2,112 |  |  |  |  |
Equity balance | $ 8,800 | $ 8,800 | $ 8,800 |  | $ 8,800 | $ 8,800 | $ 6,907 | $ 6,688

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