DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Cash and Cash Equivalents (Details) - USD ($) $ in Millions		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash and cash equivalents		$ 97.1	$ 104.3
Restricted cash		5.4	0.2
Total cash, cash equivalents and restricted cash	[1]	$ 102.5	$ 104.5	$ 87.5

[1] These amounts include restricted cash of $5.4 million and $0.2 million as of December 31, 2020 and 2019, respectively. The balance as of December 31, 2020 represents: (i) cash on deposit in lieu of a mandatory prepayment under the 2018 Foreign Asset-Based Term Facility; and (ii) cash on deposit to support outstanding undrawn letters of credit. The balance as of December 31, 2019 represents: (i) cash on deposit in lieu of a mandatory prepayment under the 2018 Foreign Asset-Based Term Facility; and (ii) cash on deposit to support outstanding undrawn letters of credit. These balances were included within prepaid expenses and other current assets and other assets in the Company's Consolidated Balance Sheets as of December 31, 2020 and December 31, 2019, respectively.