FAIR VALUE MEASUREMENTS - Recurring Fair Value Measurements (Details) - USD ($) $ in Millions	Sep. 30, 2022	Mar. 31, 2022
Assets measured at fair value on a recurring basis
Short-term investments	$ 348.0	$ 820.1
Total financial assets	1,229.9	2,619.1
Contingent earn-out consideration	(52.7)	(66.0)
Contingent earn-out consideration	(4.3)	(43.0)
Convertible notes	(52.9)
Total financial liabilities	(111.7)	(109.2)
Money market funds
Assets measured at fair value on a recurring basis
Cash and cash equivalents	16.4	501.9
Restricted cash and cash equivalents	523.7	356.8
Restricted cash and cash equivalents, long term	109.1	103.5
Bank-time deposits
Assets measured at fair value on a recurring basis
Cash and cash equivalents	206.1	636.0
Short-term investments	17.3	131.8
Restricted cash and cash equivalents	0.5	0.5
Corporate bonds
Assets measured at fair value on a recurring basis
Cash and cash equivalents		2.8
Short-term investments	311.0	538.5
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	14.7	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	(1.8)	(0.2)
Quoted prices in active markets for identical assets (level 1)
Assets measured at fair value on a recurring basis
Total financial assets	878.1	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	16.4	501.9
Restricted cash and cash equivalents	523.7	356.8
Restricted cash and cash equivalents, long term	109.1	103.5
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	206.1	636.0
Short-term investments	17.3	131.8
Restricted cash and cash equivalents	0.5	0.5
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) | 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	0.0
Significant other observable inputs (level 2)
Assets measured at fair value on a recurring basis
Total financial assets	325.7	797.1
Contingent earn-out consideration	0.0	0.0
Contingent earn-out consideration	0.0	0.0
Convertible notes	(52.9)
Total financial liabilities	(54.7)	(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) | 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) | Corporate bonds
Assets measured at fair value on a recurring basis
Cash and cash equivalents		2.8
Short-term investments	311.0	538.5
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	14.7	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	(1.8)	(0.2)
Significant unobservable inputs (level 3)
Assets measured at fair value on a recurring basis
Total financial assets	26.1	16.1
Contingent earn-out consideration	(52.7)	(66.0)
Contingent earn-out consideration	(4.3)	(43.0)
Convertible notes	0.0
Total financial liabilities	(57.0)	(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) | 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) | 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) | 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	$ 0.0