Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statements of Comprehensive Income [Abstract]
Net income	$ 7,786	$ 11,874	$ 20,206	$ 23,259
Other comprehensive income:
Change in fair value of derivative instrument, net of income tax		(28)		(233)
Comprehensive income	$ 7,786	$ 11,846	$ 20,206	$ 23,026