Joint Ventures - Schedule of Condensed Financial Statements (Details) - USD ($) $ in Millions |
Jul. 03, 2026 |
Apr. 03, 2026 |
Oct. 03, 2025 |
Jun. 27, 2025 |
Mar. 28, 2025 |
Sep. 27, 2024 |
|---|---|---|---|---|---|---|
| Variable Interest Entity [Line Items] | ||||||
| Cash and cash equivalents | $ 459 | $ 437 | ||||
| Total assets | 11,199 | 11,460 | ||||
| Current liabilities | 2,094 | 2,354 | ||||
| Total liabilities | 6,410 | 6,840 | ||||
| Total Amentum equity | 4,695 | 4,505 | ||||
| Non-controlling interests | 94 | 115 | ||||
| Total shareholders' equity | 4,789 | $ 4,703 | 4,620 | $ 4,589 | $ 4,579 | $ 4,552 |
| Total liabilities and shareholders' equity | 11,199 | 11,460 | ||||
| Variable Interest Entity, Primary Beneficiary | ||||||
| Variable Interest Entity [Line Items] | ||||||
| Cash and cash equivalents | 123 | 167 | ||||
| Current assets | 192 | 191 | ||||
| Non-current assets | 0 | 0 | ||||
| Total assets | 315 | 358 | ||||
| Current liabilities | 106 | 146 | ||||
| Non-current liabilities | 6 | 0 | ||||
| Total liabilities | 112 | 146 | ||||
| Total Amentum equity | 120 | 153 | ||||
| Non-controlling interests | 83 | 59 | ||||
| Total shareholders' equity | 203 | 212 | ||||
| Total liabilities and shareholders' equity | $ 315 | $ 358 |
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- Definition Amount of asset recognized for present right to economic benefit. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold or consumed after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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- Definition Amount of liability recognized for present obligation requiring transfer or otherwise providing economic benefit to others. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of obligation due after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of equity (deficit) attributable to noncontrolling interest. Excludes temporary equity. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of current assets classified as other. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of equity (deficit) attributable to parent and noncontrolling interest. Excludes temporary equity. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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