Share Based Compensation Arrangement, Vesting, Number of Installment Anniversaries

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

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Amount of cost for defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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

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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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- Definition

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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- Definition

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

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Stockholders' Equity and Employee Benefit Plans - Narrative (Details) shares in Thousands, $ in Millions	1 Months Ended						12 Months Ended
	Mar. 31, 2024 shares	Nov. 30, 2023 shares	Mar. 31, 2023 shares	Mar. 31, 2022 shares	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2024 USD ($) installmentAnniversary shares	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of installment anniversaries \| installmentAnniversary							3
Granted \| shares							642
Share-based compensation							$ 37	$ 28	$ 29
Unrecognized compensation expense							$ 46
Unrecognized compensation expense, weighted average period							1 year 2 months 12 days
Matching contributions amount							$ 16	11	18
Share-Based Payment Arrangement, Expense, Tax Benefit							$ 13	$ 12	$ 11
Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer percent match of contribution							100.00%
Percent match of gross pay							2.00%
Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer percent match of contribution							50.00%
Percent match of gross pay							4.00%
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted \| shares	80	200	100	100
Vesting period							3 years
Performance Stock Units \| Min
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of target awards					0.00%	0.00%
Vesting period							3 years
Performance Stock Units \| Min \| Relative TSR
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of target awards		0.00%	0.00%
Performance Stock Units \| Min \| Annualized TBV
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of target awards		0.00%	0.00%
Performance Stock Units \| Max
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of target awards					200.00%	200.00%
Vesting period							5 years
Performance Stock Units \| Max \| Relative TSR
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of target awards		200.00%	200.00%
Performance Stock Units \| Max \| Annualized TBV
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of target awards		200.00%	200.00%