Additional Financial Information (Accounts Receivable Monetization) (Details) - Trade Accounts Receivable - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Dec. 31, 2019	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Individual Monetization Agreements
Transfer of Financial Assets Accounted for as Sales [Line Items]
Net cash proceeds received		$ 1,371.3	$ 1,593.9	$ 469.2
Carrying value of receivables transferred and derecognized		1,377.2	1,603.2	473.9
Loss recorded related to transfers of receivables		5.9	9.3	$ 4.7
Derecognized accounts receivable for which the Company continues to service, amount outstanding		562.8	529.8
Pooled Monetization Agreements
Transfer of Financial Assets Accounted for as Sales [Line Items]
Gross cash proceeds received for receivables transferred and derecognized		173.1	192.6
Less amounts from collections reinvested under revolving agreement		(138.7)	(84.5)
Proceeds from new transfers		34.4	108.1
Collections not reinvested and remitted or to be remitted		(27.9)	(15.6)
Net cash proceeds received		6.5	92.5
Carrying value of receivables transferred and derecognized		172.0	191.9
Obligations recorded		1.9	2.5
Loss recorded related to transfers of receivables		0.8	1.7
Derecognized accounts receivable for which the Company continues to service, amount outstanding		99.0	$ 92.5
Revolving agreement, maximum amount of receivables allowed to transfer	$ 150.0
Accounts receivable pledged as collateral under pooled monetization agreement		$ 48.1

Cash Flows Between Transferor and Transferee, Net Proceeds (Disbursements)

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Cash flows between a transferor and a transferee attributable to collections not reinvested in revolving period transfers related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing and recourse).

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- Definition

Cash Flows Between Transferor and Transferee, Proceeds from New Transfers, Gross

+ References

No definition available.

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Securitization or Asset-backed Financing Arrangement, Collateral

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Securitization or Asset-backed Financing Arrangement, Maximum Amount of Receivables Allowed to Transfer

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Transfer of Financial Assets Accounted for as Sales, Amount Derecognized During Period

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Represents the initial fair value recorded for liabilities incurred on the transfer of financial assets in a securitization, asset-backed financing arrangement, or a similar transfer which transaction is recognized as a sale of the transferred financial assets.

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No definition available.

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Cash Flows between a transferor and a transferee attributable to collections reinvested in revolving period transfers related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 4
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Reflects, by transferred financial asset type, the amount of sales proceeds in excess of or deficient from the sum of the carrying amounts of transferred financial assets plus transaction costs, including those transactions in which the seller/transferor has continuing involvement with the financial assets that have been transferred.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719

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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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