BUSINESS COMBINATIONS - Narrative (Details) - Wavecell Pte. Ltd. $ in Millions	Jul. 17, 2019 USD ($)
Business Acquisition [Line Items]
Business combination, consideration transferred	$ 117.1
Payments to acquire business	72.8
Business combination, value of stock issued	44.3
Cash held back to cover indemnity claims	10.4
Equity held back to cover indemnity claims	$ 8.5
Vesting period	3 years
Time-Based Restricted Stock Awards
Business Acquisition [Line Items]
Business combination, value of stock issued	$ 13.2
Performance-Based Restricted Stock Awards
Business Acquisition [Line Items]
Business combination, value of stock issued	6.6
Restricted Cash, Current and Other Accrued Liabilities
Business Acquisition [Line Items]
Cash held back to cover indemnity claims	10.4
Additional paid-in capital
Business Acquisition [Line Items]
Equity held back to cover indemnity claims	$ 8.5

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