Commitment and contingencies - Capital Commitments (Details) - USD ($) $ in Millions	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Capital Commitments for Property and Equipment
Other Commitments [Line Items]
Capital commitments	$ 14.8	$ 1.2	$ 1.8
Capital Commitments for Intangible Assets
Other Commitments [Line Items]
Capital commitments	$ 1.6	$ 1.3	$ 0.9

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

No definition available.

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