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Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Mar. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments in equity and debt securities of growth stage companies | $ 111 |  | $ 103
Gains (losses) associated with equity investments | 0 | $ 110 |
Gain related to share price increase of equity securities |  | 97 |
Proceeds from sale of equity securities |  | $ 89 |
Fair value, inputs, level 1 | Fair Value, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Money market funds at carrying value | $ 242 |  | $ 1,000

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- Definition Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479536/321-10-50-4 + Details
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- Definition Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. + References No definition available. + Details
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