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Stockholders' Equity - Narrative (Details) - USD ($) |  | 3 Months Ended | 6 Months Ended | 9 Months Ended | 26 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Oct. 23, 2020 | Jun. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2020 | Sep. 30, 2019 | Jun. 30, 2020 | Jan. 24, 2020 | Apr. 23, 2018
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Shares withheld for tax withholding and exercise of options (in shares) |  |  |  |  | 9,214 | 7,795 |  |  |
Amount of shares withheld for tax withholding and exercise of options |  |  |  |  | $ 369,000 | $ 326,000 |  |  |
Shares withheld for tax withholding and exercise of options, weighted average price (in usd per share) |  |  |  |  | $ 40.01 | $ 41.84 |  |  |
Share repurchase program, amount approved to repurchase |  |  |  |  |  |  |  | $ 25,000,000.0 | $ 25,000,000.0
Stock repurchased, net of commissions |  |  | $ 2,726,000 |  | $ 3,230,000 | $ 13,170,000 | $ 25,200,000 |  |
Subsequent event |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Dividends declared per common share (in usd per share) | $ 0.23 |  |  |  |  |  |  |  |
Common Stock |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Stock repurchased, net of commissions (in shares) |  | 0 | 65,127 | 0 | 92,664 | 313,651 | 619,881 |  |
Stock repurchased, net of commissions |  |  | $ 2,726,000 |  | $ 3,230,000 | $ 13,170,000 |  |  |
Performance-based stock awards |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Vesting period of performance-based stock awards |  |  |  |  | 3 years |  |  |  |
Performance-based stock awards | Minimum |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Vesting percentage of performance-based awards |  |  |  |  | 0.00% |  |  |  |
Performance-based stock awards | Maximum |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |
Vesting percentage of performance-based awards |  |  |  |  | 200.00% |  |  |  |

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