EARNINGS PER COMMON SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Net Income
Basic earnings per share	$ 9,671	$ 39,081
Restricted stock and performance units	0	0
Diluted earnings per share	$ 9,671	$ 39,081
Shares
Basic earnings per share (in shares)	64,879,000	64,765,000
Restricted stock and performance units (in shares)	292,000	156,000
Diluted earnings per share (in shares)	65,171,000	64,921,000
Per Share Amount
Basic earnings per share (in dollars per share)	$ 0.15	$ 0.60
Restricted stock and performance units (in dollars per share)	0.00	0.00
Diluted earnings per share (in dollars per share)	$ 0.15	$ 0.60
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Outstanding stock options, excluded in the calculation of earnings per share	3,401,718	1,584,000

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Amount of Dilutive Securities Restricted Stock Units Per Share

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Incremental Common Shares Attributable to Share-based Payment Arrangements, Restricted Stock

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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