SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING PRONOUNCEMENTS (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Oct. 01, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability	$ 32,679
Operating lease, right of use asset	31,241				$ 0
Effect of the adoption of the stranded tax effect accounting standard	1,025,034	$ 1,009,410	$ 1,029,999		980,377	$ 1,025,333	$ 1,025,867	$ 1,008,167	$ 666,692
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effect of the adoption of the stranded tax effect accounting standard					0
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effect of the adoption of the stranded tax effect accounting standard	$ 529,786	$ 508,126	$ 488,187		461,501	$ 494,009	$ 487,467	$ 472,585	$ 471,673
Retained Earnings | Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Effect of the adoption of the stranded tax effect accounting standard					$ 488
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease liability				$ 30,881
Operating lease, right of use asset				$ 30,115