FAIR VALUE MEASUREMENTS - Recurring Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2022	Mar. 31, 2022
Assets measured at fair value on a recurring basis
Short-term investments	$ 459.2	$ 820.1
Capped calls	140.1
Total financial assets	1,467.5	2,619.1
Contingent earn-out consideration	(116.6)	(66.0)
Contingent earn-out consideration	(6.2)	(43.0)
Convertible notes	(54.4)
Total financial liabilities	(177.2)	(109.2)
Money market funds
Assets measured at fair value on a recurring basis
Cash and cash equivalents	14.3	501.9
Restricted cash and cash equivalents	466.8	356.8
Restricted cash and cash equivalents, long term	108.7	103.5
Corporate bonds
Assets measured at fair value on a recurring basis
Cash and cash equivalents		2.8
Short-term investments	416.2	538.5
Bank-time deposits
Assets measured at fair value on a recurring basis
Cash and cash equivalents	251.8	636.0
Short-term investments	16.1	131.8
Restricted cash and cash equivalents	0.5	0.5
US Treasuries
Assets measured at fair value on a recurring basis
Cash and cash equivalents		52.0
Short-term investments	5.0	23.4
Commercial paper
Assets measured at fair value on a recurring basis
Cash and cash equivalents		119.4
Short-term investments	21.9	125.4
Certificates of Deposit
Assets measured at fair value on a recurring basis
Cash and cash equivalents		10.0
Short-term investments		1.0
Private equity
Assets measured at fair value on a recurring basis
Private equity	26.1	16.1
Foreign currency forward contracts
Assets measured at fair value on a recurring basis
Derivative Liability		(0.2)
Quoted prices in active markets for identical assets (level 1)
Assets measured at fair value on a recurring basis
Capped calls	0.0
Total financial assets	863.2	1,805.9
Contingent earn-out consideration	0.0	0.0
Contingent earn-out consideration	0.0	0.0
Convertible notes	0.0
Total financial liabilities	0.0	0.0
Quoted prices in active markets for identical assets (level 1) | Money market funds
Assets measured at fair value on a recurring basis
Cash and cash equivalents	14.3	501.9
Restricted cash and cash equivalents	466.8	356.8
Restricted cash and cash equivalents, long term	108.7	103.5
Quoted prices in active markets for identical assets (level 1) | Corporate bonds
Assets measured at fair value on a recurring basis
Cash and cash equivalents		0.0
Short-term investments	0.0	0.0
Quoted prices in active markets for identical assets (level 1) | Bank-time deposits
Assets measured at fair value on a recurring basis
Cash and cash equivalents	251.8	636.0
Short-term investments	16.1	131.8
Restricted cash and cash equivalents	0.5	0.5
Quoted prices in active markets for identical assets (level 1) | US Treasuries
Assets measured at fair value on a recurring basis
Cash and cash equivalents		52.0
Short-term investments	5.0	23.4
Quoted prices in active markets for identical assets (level 1) | Commercial paper
Assets measured at fair value on a recurring basis
Cash and cash equivalents		0.0
Short-term investments	0.0	0.0
Quoted prices in active markets for identical assets (level 1) | Certificates of Deposit
Assets measured at fair value on a recurring basis
Cash and cash equivalents		0.0
Short-term investments		0.0
Quoted prices in active markets for identical assets (level 1) | Private equity
Assets measured at fair value on a recurring basis
Private equity	0.0	0.0
Quoted prices in active markets for identical assets (level 1) | Foreign currency forward contracts
Assets measured at fair value on a recurring basis
Derivative Liability		0.0
Significant other observable inputs (level 2)
Assets measured at fair value on a recurring basis
Capped calls	140.1
Total financial assets	578.2	797.1
Contingent earn-out consideration	0.0	0.0
Contingent earn-out consideration	0.0	0.0
Convertible notes	(54.4)
Total financial liabilities	(54.4)	(0.2)
Significant other observable inputs (level 2) | Money market funds
Assets measured at fair value on a recurring basis
Cash and cash equivalents	0.0	0.0
Restricted cash and cash equivalents	0.0	0.0
Restricted cash and cash equivalents, long term	0.0	0.0
Significant other observable inputs (level 2) | Corporate bonds
Assets measured at fair value on a recurring basis
Cash and cash equivalents		2.8
Short-term investments	416.2	538.5
Significant other observable inputs (level 2) | Bank-time deposits
Assets measured at fair value on a recurring basis
Cash and cash equivalents	0.0	0.0
Short-term investments	0.0	0.0
Restricted cash and cash equivalents	0.0	0.0
Significant other observable inputs (level 2) | US Treasuries
Assets measured at fair value on a recurring basis
Cash and cash equivalents		0.0
Short-term investments	0.0	0.0
Significant other observable inputs (level 2) | Commercial paper
Assets measured at fair value on a recurring basis
Cash and cash equivalents		119.4
Short-term investments	21.9	125.4
Significant other observable inputs (level 2) | Certificates of Deposit
Assets measured at fair value on a recurring basis
Cash and cash equivalents		10.0
Short-term investments		1.0
Significant other observable inputs (level 2) | Private equity
Assets measured at fair value on a recurring basis
Private equity	0.0	0.0
Significant other observable inputs (level 2) | Foreign currency forward contracts
Assets measured at fair value on a recurring basis
Derivative Liability		(0.2)
Significant unobservable inputs (level 3)
Assets measured at fair value on a recurring basis
Capped calls	0.0
Total financial assets	26.1	16.1
Contingent earn-out consideration	(116.6)	(66.0)
Contingent earn-out consideration	(6.2)	(43.0)
Convertible notes	0.0
Total financial liabilities	(122.8)	(109.0)
Significant unobservable inputs (level 3) | Money market funds
Assets measured at fair value on a recurring basis
Cash and cash equivalents	0.0	0.0
Restricted cash and cash equivalents	0.0	0.0
Restricted cash and cash equivalents, long term	0.0	0.0
Significant unobservable inputs (level 3) | Corporate bonds
Assets measured at fair value on a recurring basis
Cash and cash equivalents		0.0
Short-term investments	0.0	0.0
Significant unobservable inputs (level 3) | Bank-time deposits
Assets measured at fair value on a recurring basis
Cash and cash equivalents	0.0	0.0
Short-term investments	0.0	0.0
Restricted cash and cash equivalents	0.0	0.0
Significant unobservable inputs (level 3) | US Treasuries
Assets measured at fair value on a recurring basis
Cash and cash equivalents		0.0
Short-term investments	0.0	0.0
Significant unobservable inputs (level 3) | Commercial paper
Assets measured at fair value on a recurring basis
Cash and cash equivalents		0.0
Short-term investments	0.0	0.0
Significant unobservable inputs (level 3) | Certificates of Deposit
Assets measured at fair value on a recurring basis
Cash and cash equivalents		0.0
Short-term investments		0.0
Significant unobservable inputs (level 3) | Private equity
Assets measured at fair value on a recurring basis
Private equity	$ 26.1	16.1
Significant unobservable inputs (level 3) | Foreign currency forward contracts
Assets measured at fair value on a recurring basis
Derivative Liability		$ 0.0