Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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LONG-TERM DEBT / INTEREST EXPENSE - Interest Rate Swaps (Details) $ in Millions	Jun. 30, 2021 USD ($)	Feb. 28, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 13, 2018 USD ($) interest_rate_swap
Interest rate swaps
Debt Instrument [Line Items]
Number of interest rate swaps \| interest_rate_swap						2
Interest rate swap one
Debt Instrument [Line Items]
Notional amount						$ 275
Derivative interest floor rate (percentage)						0.00%
Interest rate swap one \| Forecast
Debt Instrument [Line Items]
Notional amount	$ 275
Interest rate swap two
Debt Instrument [Line Items]
Notional amount					$ 175	$ 225
Derivative interest floor rate (percentage)						0.75%
Interest rate swap two \| Forecast
Debt Instrument [Line Items]
Notional amount		$ 225	$ 75	$ 125
Maximum
Debt Instrument [Line Items]
Debt instrument fixed rate						2.82%
Minimum
Debt Instrument [Line Items]
Debt instrument fixed rate						2.74%