CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Comprehensive income:
Net income	$ 14,241	$ 12,625	$ 36,660	$ 30,256
Derivative instruments:
Reclassification of losses to net income, net of tax of $12, $12, $24 and $25, respectively	19	19	38	38
Other comprehensive income	19	19	38	38
Comprehensive income	$ 14,260	$ 12,644	$ 36,698	$ 30,294