Leases (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Mar. 31, 2023
Lease Assets and Liabilities [Abstract]
Operating lease ROU assets		$ 58.2		$ 58.2		$ 59.1
Operating lease ROU assets, Statement of Financial Position [Extensible List]		Other noncurrent assets		Other noncurrent assets		Other noncurrent assets
Finance lease ROU assets	[1]	$ 6.7		$ 6.7		$ 7.1
Finance lease ROU assets, Statement of Financial Position [Extensible List]		Property, plant and equipment - net		Property, plant and equipment - net		Property, plant and equipment - net
Operating lease liabilities, current		$ 11.8		$ 11.8		$ 11.8
Operating lease liabilities, current, Statement of Financial Position [Extensible List]		Other current liabilities		Other current liabilities		Other current liabilities
Operating lease liabilities, noncurrent		$ 47.4		$ 47.4		$ 48.9
Operating lease liabilities, noncurrent, Statement of Financial Position [Extensible List]		Other noncurrent liabilities		Other noncurrent liabilities		Other noncurrent liabilities
Finance lease liabilities, current		$ 0.4		$ 0.4		$ 0.4
Finance lease liabilities, current, Statement of Financial Position [Extensible List]		Long-term debt - current portion		Long-term debt - current portion		Long-term debt - current portion
Finance lease liabilities, noncurrent		$ 2.0		$ 2.0		$ 2.3
Finance lease liabilities, noncurrent, Statement of Financial Position [Extensible List]		Long-term debt		Long-term debt		Long-term debt
Accumulated amortization		$ 3.4		$ 3.4		$ 3.2
Components of Lease Expense [Abstract]
Operating lease expense	[2]	5.6	$ 5.5	11.5	$ 10.8
Finance lease expense [Abstract]
Depreciation of ROU assets		0.2	0.2	0.3	0.3
Interest on lease liabilities		0.1	0.1	0.1	0.1
Total lease expense		5.9	5.8	11.9	11.2
Short-term lease expense		1.4	$ 1.5	2.9	$ 2.8
Held for Sale [Member]
Lease Assets and Liabilities [Abstract]
Operating lease ROU assets		0.6		0.6
Operating lease liabilities, current		$ 0.6		$ 0.6

[1] ROU assets were recorded net of accumulated amortization of $3.4 million and $3.2 million as of September 30, 2023 and March 31, 2023, respectively.

[2] For the three and six months ended September 30, 2023, operating lease expense included short-term lease expense of $1.4 million and $2.9 million, respectively.  For the three and six months ended September 30, 2022, operating lease expense included short-term lease expense of $1.5 million and $2.8 million, respectively.  Variable lease expense was not significant.