EARNINGS PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Net income attributable to common shareholders									$ 124.1	$ 47.7	$ 60.6
Average shares outstanding - Basic									65,333	57,249	57,555
Add potential effect of exercise of stock options and other unvested equity awards									1,263	1,287	968
Average shares outstanding - Diluted									66,596	58,536	58,523
Basic net income (loss) attributable to common shareholders per common share	$ 0.79	$ 0.69	$ 0.34	$ 0.07	$ (0.16)	$ 0.34	$ 0.46	$ 0.21	$ 1.90	$ 0.83	$ 1.05
Diluted net income (loss) attributable to common shareholders per common share	$ 0.77	$ 0.68	$ 0.33	$ 0.07	$ (0.16)	$ 0.33	$ 0.45	$ 0.21	$ 1.86	$ 0.82	$ 1.04
Shares with anti-dilutive effect excluded from the computation of Diluted EPS									400	200	300