Earnings Per Share (Tables)

6 Months Ended

Jun. 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 six months ended June 30, 2018 and 2017 are as follows: 

	Quarter Ended    June 30,		Six Months Ended   June 30,
	2018	2017	2018	2017
	(Thousands of dollars)
Weighted average outstanding shares of common stock, basic	15,806	15,716	15,806	15,716
Dilutive effect of unvested restricted stock units	—	—	—	—
Weighted average outstanding shares of common stock, diluted (1)	15,806	15,716	15,806	15,716

(1) For the quarter ended June 30, 2018 and 2017, 425,317 and 438,812 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 six months ended June 30, 2018 and 2017, 14,258 and 438,812 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.