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Share Repurchase Plan (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Sep. 16, 2019
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |
Repurchased common shares (in shares) |  | 71,936 | 411,430 | 385,840 |
Cost to repurchase common shares |  | $ 2,835,000 | $ 12,559,000 | $ 15,122,000 |
September 16, 2019 Plan |  |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |  |
Stock repurchase program, authorized amount |  |  |  |  | $ 50,000,000
Repurchased common shares (in shares) | 0 |  | 411,430 |  |
Cost to repurchase common shares |  |  | $ 12,600,000 |  |
Cost to repurchase common shares (in dollars per share) |  |  | $ 30.52 |  |

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