Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Debt - Narrative (Details) - 12 months ended Mar. 31, 2020 $ in Billions	USD ($)	EUR (€)	GBP (£)
£250 million Senior notes \| Senior notes
Debt Instrument [Line Items]
Face amount \| £			£ 250,000,000
€650 million Senior notes \| Senior notes
Debt Instrument [Line Items]
Face amount \| €		€ 650,000,000
Revolving credit facility \| Line of credit
Debt Instrument [Line Items]
Debt issued \| $	$ 1.5