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Equity (Schedule of Performance Stock Activity) (Details) - $ / shares	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
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)			0
Vested (in shares)	0	0	(30,874)
Forfeited (in shares)			(132,579)
Non-vested, ending balance (in shares)	234,324		234,324
Weighted Average Grant Date Fair Value
Non-vested, beginning balance (in usd per share)			$ 8.48
Granted (in usd per share)			0.00	$ 7.62
Vested (in usd per share)			7.14
Forfeited (in usd per share)			7.24
Non-vested, ending balance (in usd per share)	$ 9.35		$ 9.35
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