Financial Instruments - Summary Of Contractual Maturities Of Cash Equivalents And Available-For-Sale Investments (Details) $ in Millions	Dec. 31, 2019 USD ($)
Amortized Cost
Mature in less than one year	$ 2,082.4
Mature in one to five years	2,595.8
Total	4,678.2
Fair Value
Mature in less than one year	2,087.7
Mature in one to five years	2,617.6
Total	$ 4,705.3

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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