EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Net income, as reported	$ 89,361	$ 86,248
Basic earnings per share
Weighted average shares of common stock outstanding-basic (in shares)	91,911,000	88,547,000
Basic (loss) earnings per common share (usd per share)	$ 0.97	$ 0.97
Diluted earnings per share
Weighted average shares of common stock outstanding-basic (in shares)	91,911,000	88,547,000
Equity forward sale agreement (in shares)	106,000	0
Other (in shares)	303,000	399,000
Weighted average shares of common stock outstanding-diluted (in shares)	92,320,000	88,946,000
Diluted (loss) earnings per common share (usd per share)	$ 0.97	$ 0.97
Anti-dilutive shares excluded from the calculation of diluted earnings per share (in shares)	0	0

Incremental Common Shares Attributable to Other Dilutive Effect

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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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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shared included in the calculation of diluted EPS as a result of the potentially dilutive effect of equity forward arrangements using the reverse treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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