Other Financial Statement Details (Details) - USD ($) $ in Millions	Mar. 31, 2018	Mar. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable amounts	$ 565.9	$ 480.5
Less allowance for doubtful accounts	2.2	2.1
Accounts receivable, net	563.7	478.4
Trade Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable amounts	557.8	473.3
Other Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivable amounts	$ 8.1	$ 7.2