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Equity (Schedule of Restricted Stock Activity) (Details) - $ / shares	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Restricted Stock Units
Number of Shares
Non-vested, beginning balance (in shares)	1,011,621
Granted (in shares)	752,416
Vested (in shares)	(321,335)
Forfeited (in shares)	(443,455)
Non-vested, ending balance (in shares)	999,247	1,011,621
Weighted Average Grant Date Fair Value
Non-vested, beginning balance (in usd per share)	$ 6.04
Weighted average fair value (in usd per share)	3.68	$ 5.80	$ 8.20
Vested (in usd per share)	5.94
Forfeited (in usd per share)	5.22
Non-vested, ending balance (in usd per share)	$ 4.66	$ 6.04
Restricted Stock
Number of Shares
Non-vested, beginning balance (in shares)	8,154
Granted (in shares)	0
Vested (in shares)	0
Forfeited (in shares)	0
Non-vested, ending balance (in shares)	8,154	8,154
Weighted Average Grant Date Fair Value
Non-vested, beginning balance (in usd per share)	$ 8.20
Weighted average fair value (in usd per share)	0.00
Vested (in usd per share)	0.00
Forfeited (in usd per share)	0.00
Non-vested, ending balance (in usd per share)	$ 8.20	$ 8.20
Minimum \| Equity Incentive Plans 2012 and 2010 \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Maximum \| Equity Incentive Plans 2012 and 2010 \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years