CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ 49,908	$ (4,698)	$ 58,110	$ 27,604
Other comprehensive income:
Unrealized gain on derivative instruments	1,132	135	1,634	3,403
Other comprehensive income	1,132	135	1,634	3,403
Comprehensive income (loss)	51,040	(4,563)	59,744	31,007
Comprehensive (income) loss attributable to non-controlling interests	(25,032)	144	(27,039)	(17,387)
Comprehensive income (loss) attributable to common stockholders	$ 26,008	$ (4,419)	$ 32,705	$ 13,620