Assets Held for Sale (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2020
Assets Held for Sale [Abstract]
Impairment of carrying value		$ (134.4)	$ 0.0	$ (134.4)	$ 0.0
ASSETS [Abstract]
Total assets held for sale		92.9		92.9		$ 0.0
LIABILITIES [Abstract]
Total liabilities held for sale		83.2		83.2		$ 0.0
Liquid-Cooled Automotive Business [Member]
Assets Held for Sale [Abstract]
Impairment of carrying value		132.7
Long-lived assets		0.0		0.0
ASSETS [Abstract]
Cash and cash equivalents		5.3		5.3
Trade accounts receivables - net		51.7		51.7
Inventories		17.7		17.7
Other current assets		11.6		11.6
Property, plant and equipment - net		132.0		132.0
Other noncurrent assets		7.3		7.3
Impairment of carrying value		(132.7)		(132.7)
Total assets held for sale		92.9		92.9
LIABILITIES [Abstract]
Short-term debt		6.0		6.0
Accounts payable		36.9		36.9
Accrued compensation and employee benefits		10.2		10.2
Other current liabilities		12.7		12.7
Pensions		12.4		12.4
Other noncurrent liabilities		5.0		5.0
Total liabilities held for sale		83.2		$ 83.2
Liquid-Cooled Automotive Business [Member] | Forecast [Member] | Minimum [Member]
LIABILITIES [Abstract]
Loss on sale of transaction	$ 15.0
Liquid-Cooled Automotive Business [Member] | Forecast [Member] | Maximum [Member]
LIABILITIES [Abstract]
Loss on sale of transaction	$ 25.0
Automotive [Member]
Assets Held for Sale [Abstract]
Impairment of carrying value		$ 1.7