Financial Instruments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Mar. 31, 2025	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Impaired loan receivable	$ 20.0		$ 20.0
Level 3
Financing Receivable, Allowance for Credit Loss [Line Items]
Convertible loans receivable	34.0		34.0
Convertible loans receivable | Level 3
Financing Receivable, Allowance for Credit Loss [Line Items]
Fair value losses recognized in the Condensed Consolidated Income Statements	0.0	$ 1.0
Loans receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and other receivables carried at amortized cost	27.0		27.0
Arduino
Financing Receivable, Allowance for Credit Loss [Line Items]
Impaired loan receivable	$ 16.8		$ 16.6
Cerfe Labs, Inc. | Loans receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan term	4 years		4 years
Loans and other receivables carried at amortized cost	$ 3.2		$ 3.2
Allia Limited | Loans receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan term	5 years		5 years
Loans and other receivables carried at amortized cost	$ 7.5		$ 7.1
Ampere
Financing Receivable, Allowance for Credit Loss [Line Items]
Convertible loans receivable				$ 29.0
Ampere | Convertible loans receivable | Level 3
Financing Receivable, Allowance for Credit Loss [Line Items]
Fair value losses recognized in the Condensed Consolidated Income Statements	$ 0.4	$ 1.0