Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2018

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, 2018 and 2017 are as follows: 

	Quarter Ended    September 30,		Nine Months Ended   September 30,
	2018	2017	2018	2017
	(Thousands of dollars)
Weighted average outstanding shares of common stock, basic	15,816	15,799	15,811	15,750
Dilutive effect of unvested restricted stock units	—	—	—	—
Weighted average outstanding shares of common stock, diluted (1)	15,816	15,799	15,811	15,750

(1) For the quarters ended September 30, 2018 and 2017, 108,424 and -0- 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 on both September 30, 2018 and 2017, -0- unvested restricted stock units were excluded from the weighted average outstanding shares of common stock, diluted, as they were anti-dilutive to earnings per share.