COMMITMENTS AND CONTINGENCIES - Narrative (Details) - USD ($) $ in Millions		6 Months Ended
Sep. 23, 2019	Jun. 30, 2020
Loss Contingencies [Line Items]
Purchase commitments		$ 293.8
Financing of acquisition of software		$ 97.6
Period of vendor financing arrangement		2 years
Purchase commitments due remainder of 2020		$ 29.7
Purchase commitments due in 2021		64.9
Purchase commitments due in 2022		66.9
Purchase commitments due in 2023		$ 16.8
Frontline Case \| Performance Guarantee
Loss Contingencies [Line Items]
Damages awarded	$ 135.2

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Amount of damages awarded to the plaintiff in the legal matter.

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