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Equity (Schedule of Restricted Stock Activity) (Details) - $ / shares	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Restricted Stock Units
Number of Shares
Non-vested, beginning balance (in shares)	999,247
Granted (in shares)	1,215,810
Vested (in shares)	(471,208)
Forfeited (in shares)	(195,804)
Non-vested, ending balance (in shares)	1,548,045	999,247
Weighted Average Grant Date Fair Value
Non-vested, beginning balance (in usd per share)	$ 4.66
Weighted average fair value (in usd per share)	2.88	$ 3.68	$ 5.80
Vested (in usd per share)	4.50
Forfeited (in usd per share)	3.85
Non-vested, ending balance (in usd per share)	$ 3.41	$ 4.66
Restricted Stock
Number of Shares
Non-vested, beginning balance (in shares)	8,154
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
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