Earnings per Share - EPS Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income	$ (6.9)	$ 6.3
Less: Net income allocated to participating securities	0.0	(0.1)
Net income allocated to common shareholders	$ (6.9)	$ 6.2
Weighted average number of common shares outstanding	18,419,072	18,248,244
Dilutive potential common shares outstanding:
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	0	236,751
Diluted weighted-average shares	18,419,072	18,484,995