Stock-Based Compensation

9 Months Ended

Sep. 30, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation

STOCK-BASED COMPENSATION

We recognize the cost of employee compensation received in the form of equity instruments based on the grant date fair value of those awards. The table below sets forth the total amount of stock-based compensation expense for the quarter and nine months ended September 30, 2018 and 2017. 

	Quarter Ended    September 30,				Nine Months Ended   September 30,
	2018		2017		2018		2017
	(Thousands of dollars)
Stock-based compensation expense:
Time-based restricted stock units	$	1,085	$	582	$	2,162	$	1,678
Performance-based restricted stock units	1,033		689		2,088		1,396
Total stock-based compensation expense	$	2,118	$	1,271	$	4,250	$	3,074

During the quarter and nine months ended September 30, 2018, 5,001 and 326,832 time-based restricted units, respectively and -0- and 448,012 performance-based restricted units, respectively, were awarded to managerial employees.

During the quarter and nine months ended September 30, 2017, 26,296 and 472,913 time-based restricted units, respectively and 4,646 and 371,045 performance-based restricted units were awarded to managerial employees, respectively.