FINANCIAL INSTRUMENTS - Summary of Contractual Maturities of Cash Equivalents and Available-For-Sale Investments (Details) $ in Millions	Mar. 31, 2021 USD ($)
Amortized Cost
Mature in less than one year	$ 3,166.6
Mature in one to five years	2,655.8
Total	5,822.4
Fair Value
Mature in less than one year	3,175.2
Mature in one to five years	2,673.0
Total	$ 5,848.2

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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