FINANCIAL INSTRUMENTS - Summary of Contractual Maturities of Cash Equivalents and Available-For-Sale Investments (Details) $ in Millions	Sep. 30, 2019 USD ($)
Amortized Cost
Mature in less than one year	$ 1,976.2
Mature in one to five years	2,459.4
Total	4,435.6
Fair Value
Mature in less than one year	1,980.0
Mature in one to five years	2,484.0
Total	$ 4,464.0

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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