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Share Repurchase Plan (Details) - USD ($) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020 | Mar. 15, 2021
Equity, Class of Treasury Stock [Line Items] |  |  |  |
Repurchased common shares (in shares) |  | 411,430 |  |
Cost to repurchase common shares |  | $ 12,559,000 |  |
September 16, 2019 Plan |  |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |  |
Stock repurchase program, authorized amount |  |  |  | $ 50,000,000
Stock repurchase program, remaining authorized repurchase amount | $ 37,400,000 |  |  |
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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