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Equity (Schedule of Performance Stock Activity) (Details) - $ / shares	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount considered issued and outstanding (as percentage of target number of shares)	200.00%
Number of Shares
Non-vested, beginning balance (in shares)	397,777
Granted (in shares)	280,000
Vested (in shares)	(30,874)		0
Forfeited (in shares)	(175,079)
Non-vested, ending balance (in shares)	471,824	397,777
Weighted Average Grant Date Fair Value
Non-vested, beginning balance (in usd per share)	$ 8.48
Granted (in usd per share)	5.19	$ 7.62
Vested (in usd per share)	7.14
Forfeited (in usd per share)	7.36
Non-vested, ending balance (in usd per share)	$ 7.03	$ 8.48
Performance Stock Awards
Number of Shares
Non-vested, beginning balance (in shares)	33,333
Granted (in shares)	0
Vested (in shares)	0
Forfeited (in shares)	0
Non-vested, ending balance (in shares)	33,333	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)	0.00
Non-vested, ending balance (in usd per share)	$ 12.25	$ 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