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Fixed interest rate related to the interest rate derivative.

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Nominal or face amount used to calculate payment on derivative.

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FINANCIAL INSTRUMENTS - Narrative (Detail) $ in Millions	12 Months Ended
FINANCIAL INSTRUMENTS - Narrative (Detail) $ in Millions	Dec. 31, 2020 USD ($) customer	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Derivative [Line Items]
Concentration risk, percentage	99.00%
USD Interest Rate Swap Contract One
Derivative [Line Items]
Derivative, notional amount	$ 50.0
Derivative, fixed interest rate	2.878%
USD Interest Rate Swap Contract Two
Derivative [Line Items]
Derivative, notional amount	$ 50.0
Derivative, fixed interest rate	2.878%
Revenue Benchmark
Derivative [Line Items]
Number of customers \| customer	3
Concentration risk, percentage	22.20%	23.60%	23.00%
Accounts Receivable
Derivative [Line Items]
Concentration risk, percentage	2.60%	5.60%
Accumulated Translation Adjustment
Derivative [Line Items]
Foreign currency (losses) gains of net investment hedges included in accumulated other comprehensive loss	$ (66.2)	$ 6.8	$ 16.6