Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Increase (Decrease) in Stockholders' Equity [Roll Forward] | |||
| Payment of dividends (dollars per share) | $ 0.13 | $ 0.30 | $ 0.30 |
| Issuance of shares of common stock from the treasury (in shares) | 58,532 | 62,124 | 26,118 |
| Stock options exercised, net (shares) | 5,389 | 0 | 666 |
| Issuance of common stock (shares) | 0 | 0 | 0 |
| Shares of common stock purchased | 0 | 29,500 | 100,400 |
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- Definition Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Net No definition available.
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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Number of new stock issued during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of treasury shares (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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