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NOTES PAYABLE, FINANCE LEASES, AND COMMERCIAL BANK FINANCING - STG Notes (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	May 21, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Gain on extinguishment of debt		$ 0.0	$ 0.0	$ 5.0	$ 0.0
Senior Notes \| 5.875% Senior Unsecured Notes due 2026
Debt Instrument [Line Items]
Redeemed amount	$ 2.5
Interest rate (as a percent)		5.875%		5.875%
Consideration	$ 2.3
Gain on extinguishment of debt		$ 0.2
Notes balance, net of deferred financing costs		$ 344.0		$ 344.0