Stock-based compensation - Additional information (Details) - Two Thousand and Twenty Two Nextpower Plan $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended
Dec. 31, 2025 USD ($) $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation cost \| $	$ 200.1
Weighted-average period over which cost not yet recognized is expected to be recognized	2 years 1 month 6 days
Common stock equivalents from RSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period (in shares) \| shares	1.5
Award vesting period	3 years
Granted (in USD per share)	$ 64.35
PSU
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period (in shares) \| shares	0.4
Granted (in USD per share)	$ 76.04
Employee Stock Option
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, options, grants in period, gross (in shares) \| shares	0.2
Share-based compensation arrangement, option, exercise price range, outstanding, weighted average exercise price (in USD per share)	$ 56.05
Weighted average grant date fair values (in USD per share)	$ 32.60
Minimum \| PSU
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Range of options awards vesting percentage	0.00%
Maximum \| PSU
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Range of options awards vesting percentage	300.00%

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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Gross number of share options (or share units) granted during the period.

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