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Equity (Schedule of Performance Stock Activity) (Details) - $ / shares	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Performance Stock Units
Number of Shares
Non-vested, beginning balance (in shares)	471,824
Granted (in shares)	496,000
Vested (in shares)	0
Forfeited (in shares)	(99,324)
Non-vested, ending balance (in shares)	868,500	471,824
Weighted Average Grant Date Fair Value
Non-vested, beginning balance (in usd per share)	$ 7.03
Granted (in usd per share)	3.81	$ 5.19	$ 7.62
Vested (in usd per share)	0.00
Forfeited (in usd per share)	10.55
Non-vested, ending balance (in usd per share)	$ 4.79	$ 7.03
Performance Stock Awards
Number of Shares
Non-vested, beginning balance (in shares)	33,333
Forfeited (in shares)	(33,333)
Non-vested, ending balance (in shares)		33,333
Weighted Average Grant Date Fair Value
Non-vested, beginning balance (in usd per share)	$ 12.25
Granted (in usd per share)	0.00
Vested (in usd per share)	0.00
Forfeited (in usd per share)	12.25
Non-vested, ending balance (in usd per share)	$ 0.00	$ 12.25
Two Thousand Twelve Equity Incentive Plan \| Minimum \| Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	1 year
Two Thousand Twelve Equity Incentive Plan \| Maximum \| Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years