FINANCIAL INSTRUMENTS - Summary of Contractual Maturities of Cash Equivalents and Available-For-Sale Investments (Details) $ in Millions	Mar. 31, 2020 USD ($)
Amortized Cost
Mature in less than one year	$ 2,020.0
Mature in one to five years	2,605.6
Total	4,625.6
Fair Value
Mature in less than one year	2,029.6
Mature in one to five years	2,642.7
Total	$ 4,672.3

Available For Sale Securities Debt Maturities Fair Value Total

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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