Number Of Executive Awards

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Aggregate Nominal Amount, Limit, Percent

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Share-Based Compensation Arrangement By Share-Based Payment Award, Annual Increase In Shares Authorized

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Issued In Connection With The IPO

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No definition available.

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- Definition

Share-based Compensation Arrangement By Share-Based Payment Award, Maximum Employee Subscription Amount

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No definition available.

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Share-Based Compensation Arrangement By Share-Based Payment Award, Purchase Period

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No definition available.

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- Definition

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer), including liabilities for compensation costs, fringe benefits other than pension and postretirement obligations, rent, contractual rights and obligations, and statutory obligations.

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Amount of excess of issue price over par or stated value of stock and from other transaction involving stock or stockholder. Includes, but is not limited to, additional paid-in capital (APIC) for common and preferred stock.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of cost capitalized for award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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No definition available.

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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Discount rate from fair value on purchase date that participants pay for shares.

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The number of grants made 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).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Amount of cash paid to settle liability for award under share-based payment arrangement.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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Number of grantees affected by modification of award under share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Number of shares issued under share-based payment arrangement.

+ References

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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Section 50
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Share-based Compensation - Narrative (Details)			1 Months Ended					12 Months Ended
Share-based Compensation - Narrative (Details)	Apr. 01, 2025 shares	Sep. 18, 2023 USD ($) employee $ / shares shares	Sep. 30, 2024 USD ($)	Aug. 31, 2024	Oct. 31, 2023	Aug. 31, 2023 shares	Jun. 30, 2022 executive_award	Mar. 31, 2026 USD ($) shares	Mar. 31, 2025 USD ($) shares	Mar. 31, 2024 USD ($) employee shares
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Additional paid-in capital								$ 3,467,000,000	$ 2,922,000,000
Staff costs: Share-based compensation cost (equity settled)								1,052,000,000	820,000,000	$ 1,070,000,000
Accrued compensation and benefits and share-based compensation increase (decrease)								154,000,000	140,000,000
Share based payment arrangement amount capitalized								3,800,000	0	0
Share-based compensation, tax benefit (expense)								48,200,000	108,700,000	206,200,000
IPO
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Sale of stock (in dollars per share) \| $ / shares		$ 51.00
2019 AEP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Staff costs: Share-based compensation cost (equity settled)										$ 217,200,000
Number of grantees affected by modification \| employee										5,251
2019 AEP \| Reclassification, Other Noncurrent Liabilities
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Additional paid-in capital										$ 306,600,000
Non-current portion of accrued compensation and share-based compensation increase (decrease)										(306,600,000)
2019 EIP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share-based awards, liability paid								0	$ 0	0
Staff costs: Share-based compensation cost (equity settled)		$ 4,100,000
2019 EIP \| Reclassification, Other Noncurrent Liabilities
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Additional paid-in capital										5,700,000
Non-current portion of accrued compensation and share-based compensation increase (decrease)										(5,700,000)
2022 RSU Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of executive awards \| executive_award							2
Omnibus Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized share-based compensation								$ 1,719,300,000
Unrecognized share-based compensation, recognition period								1 year 2 months 12 days
Shares authorized (in shares) \| shares						20,500,000
Aggregate increased ordinary shares (in shares) \| shares	8,452,110
Annual increase in shares authorized	0.80%					2.00%
Restricted Stock Units (RSUs) \| 2019 AEP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting								100.00%
Aggregate nominal amount, limit								2.20%
Share-based awards, liability paid										$ 18,200,000
Restricted Stock Units (RSUs) \| 2019 EIP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Aggregate nominal amount, limit								30.00%
Restricted Stock Units (RSUs) \| 2022 RSU Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Aggregate nominal amount, limit							4.00%
Accelerated share-based compensation		$ 17,700,000
Number of grantees affected by modification \| employee		5,041
Unrecognized share-based compensation, recognition period								1 month 6 days
Restricted Stock Units (RSUs) \| Arm Non-Executive Directors RSU Award Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Outstanding (in shares) \| shares										31,806
Granted (in shares) \| shares										31,806
Restricted Stock Units (RSUs) \| Omnibus Incentive Plan \| Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period					3 years
Restricted Stock Units (RSUs) \| Omnibus Incentive Plan \| Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period					4 years
Restricted Stock Units, Launch Awards \| 2022 RSU Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period							3 years
Restricted Stock Units, Continuous Service \| 2022 RSU Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period							3 years
Restricted Stock Units, Time-Based \| 2022 RSU Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period							3 years
Performance Shares, Continuous Service And Performance Conditions \| 2022 RSU Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Service period							1 year
Performance Shares, Continuous Service And Performance Conditions \| Omnibus Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Service period					1 year
Performance Shares, Continuous Service And Performance Conditions \| Omnibus Incentive Plan \| Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting					0.00%
Performance Shares, Continuous Service And Performance Conditions \| Omnibus Incentive Plan \| Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting					200.00%
Restricted Stock Units, Annual Awards \| 2022 RSU Plan \| Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting							0.00%
Restricted Stock Units, Annual Awards \| 2022 RSU Plan \| Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting							200.00%
Executive Awards \| 2022 RSU Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Staff costs: Share-based compensation cost (equity settled)		$ 9,800,000
Number of grantees affected by modification \| employee		14
Vested (in shares) \| shares								(6,000,000)
Shares issued (in shares) \| shares		1,875,202
Unrecognized share-based compensation								$ 31,100,000
Outstanding (in shares) \| shares								1,000,000	7,000,000
Executive Awards \| 2022 RSU Plan \| Reclassification, Other Noncurrent Liabilities
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Additional paid-in capital		$ 20,200,000
Non-current portion of accrued compensation and share-based compensation increase (decrease)		(20,200,000)
Executive Awards \| 2022 RSU Plan \| Reclassification, Other Current Liabilities
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Additional paid-in capital		9,100,000
Accrued compensation and benefits and share-based compensation increase (decrease)		$ (9,100,000)
Performance Shares \| Omnibus Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period					3 years
Performance Shares, Time Based \| Omnibus Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period					3 years
Performance Shares, Continuous Service And Relative TSR
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period								3 years
Performance Shares, Continuous Service And Relative TSR \| Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting								0.00%
Performance Shares, Continuous Service And Relative TSR \| Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting								200.00%
Employee Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized share-based compensation								$ 13,300,000
Share based compensation arrangement maximum employee subscription rate			10.00%
Maximum employee subscription amount			$ 25,000
Discount percent			15.00%
Shares issued in period (in shares) \| shares								700,000
Employee Stock \| Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Duration of each purchase period under the ESPP				6 months
Employee Stock \| Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Duration of each purchase period under the ESPP				24 months