SUMMARY OF ACCOUNTING POLICIES - Other Current Assets and Investments (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Jun. 29, 2018	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Investments in non-consolidated companies		$ 102.8	$ 128.1
Equity in earnings		83.5	5.0	$ (6.0)
Non-core investment impairment charges		36.5
Investment impairments and dispositions		36.5	97.7	193.1
Gain on deconsolidation		0.0	0.0	87.0
Other nonoperating income (expense)		67.0	(82.0)	(120.0)
Bright Machines
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Investments in non-consolidated companies	$ 128.0
Non-core investment impairment charges		$ 35.0
Transfer of employees and equipment, net book value	$ 35.0
Gain on deconsolidation				$ 87.0
Business combination, consideration transferred			44.0
Other nonoperating income (expense)			$ (23.0)

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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