CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands	Total	Common Stock	Paid in Capital	Accumulated Deficit
Beginning balance (in shares) at Sep. 30, 2015		32,661
Beginning balance at Sep. 30, 2015	$ 630,423,000	$ 33,000	$ 857,553,000	$ (227,163,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	4,693,000			4,693,000
Amortization of nonvested stock awards	7,959,000		7,959,000
Shares issued under employee stock plans, net (in shares)		491
Shares issued under employee stock plans, net	0	$ 0	0
Forfeiture of restricted stock (in shares)		(64)
Forfeiture of restricted stock	0
Common stock redeemed (in shares)		(17)
Common stock redeemed	(222,000)		(222,000)
Ending balance (in shares) at Sep. 30, 2016		33,071
Ending balance at Sep. 30, 2016	642,853,000	$ 33,000	865,290,000	(222,470,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	31,813,000			31,813,000
Amortization of nonvested stock awards	8,164,000		8,164,000
Exercises of stock options (in shares)		2
Exercises of stock options	24,000		24,000
Shares issued under employee stock plans, net (in shares)		536
Shares issued under employee stock plans, net	1,000	$ 1,000
Forfeiture of restricted stock (in shares)		(61)
Forfeiture of restricted stock	0
Common stock redeemed (in shares)		(32)
Common stock redeemed	(415,000)		(415,000)
Ending balance (in shares) at Sep. 30, 2017		33,516
Ending balance at Sep. 30, 2017	682,440,000	$ 34,000	873,063,000	(190,657,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(45,375,000)			(45,375,000)
Amortization of nonvested stock awards	10,258,000		10,258,000
Exercises of stock options (in shares)		8
Exercises of stock options	64,000		64,000
Shares issued under employee stock plans, net (in shares)		443
Forfeiture of restricted stock (in shares)		(216)
Forfeiture of restricted stock	0
Common stock redeemed (in shares)		(229)
Common stock redeemed	(3,378,000)		(3,378,000)
Other activity	18,000	$ 0	18,000
Ending balance (in shares) at Sep. 30, 2018		33,522
Ending balance at Sep. 30, 2018	$ 644,027,000	$ 34,000	$ 880,025,000	$ (236,032,000)