DERIVATIVE INSTRUMENTS - EFFECT OF DERIVATIVE INSTRUMENTS DESIGNATED AS CASH FLOW HEDGES ON OCI (Details) - Treasury Lock - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Derivative [Line Items]
Amount of Gain or (Loss) Recognized in OCI on Derivatives (Effective Portion)	$ (12,492)	$ 0	$ (12,492)	$ 0
Interest Expense
Derivative [Line Items]
Amount of Gain or (Loss) Reclassified from OCI into Income (Effective Portion)	$ 0	$ 0	$ 0	$ 0