Cash, Cash Equivalents and Marketable Securities - Schedule of Cash, Cash Equivalents, and Marketable Securities (Details) - USD ($) $ in Thousands |
Sep. 30, 2026 |
Mar. 31, 2026 |
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| Cash and cash equivalents: | ||
| Cash | $ 166,807 | $ 44,526 |
| Money market funds | 1,475,459 | 1,374,706 |
| Total cash and cash equivalents | 1,642,266 | 1,419,232 |
| Marketable securities: | ||
| Debt securities, available-for-sale | 2,565,320 | 2,872,601 |
| Total cash, cash equivalents and marketable securities | 4,207,586 | 4,291,833 |
| U.S. Treasury securities | ||
| Marketable securities: | ||
| Debt securities, available-for-sale | 1,879,322 | 2,124,179 |
| Corporate bonds | ||
| Marketable securities: | ||
| Debt securities, available-for-sale | 668,432 | 748,422 |
| Commercial paper | ||
| Marketable securities: | ||
| Debt securities, available-for-sale | $ 17,566 | $ 0 |
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means 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. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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