CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 16,630	$ 4,986
Other comprehensive income (loss):
Unrealized income on derivative instruments designated as cash flow hedges	84	725
Reclassification adjustment realized in net income (effective portion)	(12)	894
Total other comprehensive income	72	1,619
Total comprehensive income	16,702	6,605
Total comprehensive income attributable to noncontrolling interest	0	0
Total comprehensive income attributable to common stockholders	$ 16,702	$ 6,605