BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Income Taxes (Details) $ in Millions	3 Months Ended
Dec. 31, 2017 USD ($)
Accounting Policies [Abstract]
Provisional income tax benefit related to 2017 US Tax Reform Act	$ 158.7

Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)

No definition available.

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