EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Earnings Per Share [Abstract]
Net (loss) income, as reported		$ (7,460)	$ (14,274)	$ 176,763	$ 166,390
Basic earnings per share
Weighted average shares of common stock outstanding-basic (shares)		85,449,000	84,234,000	85,110,000	84,144,000
Basic (loss) earnings per common share (usd per share)		$ (0.09)	$ (0.17)	$ 2.08	$ 1.98
Incremental shares (1)	[1]	0	0	1,018,000	768,000
Diluted earnings per share
Weighted average shares of common stock outstanding-diluted (shares)		85,449,000	84,234,000	86,128,000	84,912,000
Diluted (loss) earnings per common share (usd per share)	[2]	$ (0.09)	$ (0.17)	$ 2.05	$ 1.96
Anti-dilutive shares excluded from the calculation of diluted earnings per share		1,018,000	768,000	0	0

[1] Incremental shares consist primarily of stock awards and performance shares.

[2] Since there was a net loss for the three months ended June 30, 2015, and 2014, incremental shares of 1,018 and 768, respectively, were not included in the computation of diluted loss per common share, as their effect would have been anti-dilutive. There were no anti-dilutive shares excluded from the calculation of diluted earnings per share for the nine months ended June 30, 2015, and 2014.