Significant Accounting Policies, Trade Accounts Receivable (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Trade Accounts Receivable [Abstract]
Trade receivables, allowance for credit losses	$ (1.3)	$ (1.9)
Trade receivables sold without recourse	88.7	75.4	$ 85.1
Loss on the sale of accounts receivables	$ (0.2)	$ (0.5)	$ (0.6)