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Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Feb. 28, 2019 | Sep. 30, 2002 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Class of Stock [Line Items] |  |  |  |  |
Dividends paid to shareholders |  |  | $ 7,064 | $ 5,965 | $ 5,372
Cash dividends paid (in USD per share) |  |  | $ 1.02 | $ 0.86 | $ 0.78
Percentage of common stock authorized for repurchase |  | 5.00% |  |  |
Remaining shares available under stock repurchase program (in shares) |  |  | 153,433 |  |
Shares repurchased (in shares) |  |  | 15,468 | 58,341 | 0
Subsequent Event |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Cash dividends declared (in USD per share) | $ 0.30 |  |  |  |

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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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