MARKETABLE SECURITIES - Contractual Maturities of Available-for-Sale Debt Securities (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Amortized Cost
Less than one year	$ 27.0
One to five years	61.9
Six to ten years	36.3
Greater than ten years	86.2
Amortized Cost	211.4	$ 214.5
Fair Value
Less than one year	27.0
One to five years	61.6
Six to ten years	35.5
Greater than ten years	84.2
Fair Value	$ 208.3	$ 219.4

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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