v3.4.0.3

Earnings Per Share (Tables) | 3 Months Ended
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Mar. 31, 2016
Earnings Per Share [Abstract] |
Components of Basic and Diluted Earnings Per Share | The components of basic and diluted earnings per share are as follows:
|  | Quarter Ended March |
|  | 2016 |  |  | 2015 |
|  | (Thousands of dollars) |
Weighted average outstanding shares of common stock, basic |  |  | 15,600 |  |  |  | 15,579 |
Dilutive effect of unvested restricted stock units |  |  | — |  |  |  | 83 |
Weighted average outstanding shares of common stock, diluted |  |  | 15,600 |  |  |  | 15,662 |

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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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