Additional Financial Information (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Dec. 31, 2018	Dec. 31, 2018	Mar. 31, 2018
Transfer of Financial Assets Accounted for as Sales [Line Items]
Cash proceeds from transfer of receivables	$ 131.1	$ 131.1
Loss recorded	1.8	1.8
Restricted cash	0.0	0.0	$ 0.0
Trade Accounts Receivable
Transfer of Financial Assets Accounted for as Sales [Line Items]
Receivables monetized, amount derecognized	132.9	132.9
Derecognized accounts receivable for which the Company continues to service, amount outstanding	$ 125.9	$ 125.9

Amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction that have been derecognized. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Reflects the net positive or negative amount derived from subtracting from net proceeds of sale, the carrying amounts, net of allocated reserves, of accounts receivable transferred to a third party in a transaction that qualifies for sales treatment.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of derecognized financial assets from transactions which comprise an initial transfer and an agreement entered into in contemplation of the initial transfer resulting in retention of substantially all of the exposure to the economic return throughout the term of the transaction, at the date of derecognition.

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Amount, before counterparty netting, of cash proceeds received in transfers of derecognized financial assets from transactions which comprise an initial transfer and an agreement entered into in contemplation of the initial transfer resulting in retention of substantially all of the exposure to the economic return throughout the term of the transaction.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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