v3.8.0.1

Earnings Per Share (Tables) | 9 Months Ended
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Sep. 30, 2017
Earnings Per Share [Abstract] |
Components of Basic and Diluted Earnings Per Share | The components of basic and diluted earnings per share for the quarter and nine months ended September 30, 2017 and 2016 are as follows:
|  | Quarter Ended September 30, |  | Nine Months Ended September 30,
|  | 2017 |  | 2016 |  | 2017 |  | 2016
|  | (Thousands of dollars)
Weighted average outstanding shares of common stock, basic |  | 15,799 |  |  | 15,683 |  |  | 15,750 |  |  | 15,655 |
Dilutive effect of unvested restricted stock units |  | — |  |  | — |  |  | — |  |  | — |
Weighted average outstanding shares of common stock, diluted (1) |  | 15,799 |  |  | 15,683 |  |  | 15,750 |  |  | 15,655 |
(1) | For the three months ended September 30, 2017 and 2016, 0 and 52,126 unvested restricted stock units were excluded from the weighted average outstanding shares of common stock, diluted, respectively as they were anti-dilutive to earnings per share. For the nine months ended September 30, 2017 and 2016, 0 and 22,221 unvested restricted stock units were excluded from the weighted average outstanding shares of common stock, diluted, respectively as they were anti-dilutive to earnings per share.

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- Definition Tabular disclosure of the weighted average number of shares used in calculating basic net earnings per share (or unit) and diluted earnings per share (or unit). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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