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Share-based Compensation - Narrative (Details) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jul. 31, 2019 | Mar. 31, 2024 | Mar. 31, 2023 | Mar. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Income tax benefit recognized on shares-based compensation arrangements |  | $ 64,100,000 | $ 38,100,000 | $ 43,100,000
Aggregate intrinsic value of options exercised |  | 46,100,000 | 37,900,000 | 52,600,000
Aggregate fair value of options vested |  | 9,100,000 | $ 16,700,000 | $ 23,100,000
Total unrecognized compensation expense related to non-vested stock options |  | $ 1,400,000 |  |
Options |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted average grant date fair value of options granted (in dollars per share) |  |  |  | $ 20.90
Options granted (in shares) |  | 0 | 0 |
Weighted average period of recognition |  | 6 months |  |
Expected dividend yield |  | $ 0 |  | $ 0
RSUs |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted average period of recognition |  | 2 years 1 month 6 days |  |
RSUs outstanding (in shares) |  | 9,852,000 | 8,836,000 |
Weighted average grant-date fair value of units granted (in dollars per share) |  | $ 51.60 | $ 40.42 | $ 50.19
Awards granted (in shares) |  | 6,193,000 |  |
Aggregate fair value of awards/units vested |  | $ 220,300,000 | $ 82,100,000 | $ 72,200,000
Total unrecognized compensation expense related to unvested awards/units |  | $ 375,400,000 |  |
Service Condition RSUs |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
RSUs outstanding (in shares) |  | 8,900,000 |  |
Service and performance condition RSUs |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
RSUs outstanding (in shares) |  | 900,000 |  |
Maximum percentage of shares issued based on performance target award |  | 2 |  |
RSAs |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Weighted average period of recognition |  | 2 years 10 months 24 days |  |
RSUs outstanding (in shares) |  | 142,000 | 4,000 |
Weighted average grant-date fair value of units granted (in dollars per share) |  | $ 49.05 |  |
Awards granted (in shares) |  | 142,000 | 0 | 0
Aggregate fair value of awards/units vested |  | $ 200,000 | $ 6,800,000 | $ 27,700,000
Total unrecognized compensation expense related to unvested awards/units |  | $ 8,700,000 |  |
Shares committed under ESPP |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Shares reserved and available for issuance as a percentage of shares outstanding | 1.00% |  |  |
Increase In the number of shares reserved and available for issuance (in shares) | 3,500,000 |  |  |
ESPP offering period | 6 months |  |  |
Purchase period | 6 months |  |  |
Shares committed under ESPP | Common Class A |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
ESPP, maximum percentage of the common stock available for purchase | 85.00% |  |  |
Share-based Payment Arrangement, Tranche One | Service and performance condition RSUs |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  | 1 year |  |
Vesting percentage |  | 33.00% |  |
Share-based Payment Arrangement, Tranche Two | Service and performance condition RSUs |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  | 2 years |  |
Vesting percentage |  | 67.00% |  |
Minimum | Performance-based Awards |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  | 3 years |  |
Maximum | Performance-based Awards |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  | 4 years |  |
2019 Plan |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Common stock reserved for future issuance (in shares) | 52,000,000 | 49,844,520 |  |
Annual increase percentage in shares reserved for future issuance based off of shares outstanding | 4.00% |  |  |
2019 Plan | Share-based Payment Arrangement, Tranche One |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  | 1 year |  |
Vesting percentage |  | 33.00% |  |
2019 Plan | Share-based Payment Arrangement, Tranche Two |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  | 1 year |  |
Vesting percentage |  | 25.00% |  |
2019 Plan | Minimum |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  | 3 years |  |
2019 Plan | Minimum | Share-based Payment Arrangement, Tranche Three |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  | 2 years |  |
2019 Plan | Maximum |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  | 4 years |  |
2019 Plan | Maximum | Share-based Payment Arrangement, Tranche Three |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award vesting period |  | 3 years |  |
ESPP |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Expected dividend yield |  | $ 0 | $ 0 | $ 0
Total unrecognized compensation expense related to unvested awards/units |  | $ 1,200,000 |  |
ESPP | Common Class A |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Common stock reserved for future issuance (in shares) |  | 15,865,787 |  |
Issuance of common stock related to employee stock purchase plan (in shares) |  | 534,022 |  |

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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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