Acquisitions and Divestitures (Pro Forma Information) (Details) - Entrust - USD ($) $ / shares in Units, $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jul. 03, 2026 |
Jul. 04, 2025 |
Jul. 03, 2026 |
Jul. 04, 2025 |
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| Business Combination [Line Items] | ||||
| Revenues | $ 4,558 | $ 4,394 | $ 9,086 | $ 8,772 |
| Net income | 355 | 390 | 697 | 730 |
| Net income attributable to Leidos common stockholders | $ 353 | $ 388 | $ 688 | $ 726 |
| Basic (in dollars per share) | $ 2.80 | $ 3.01 | $ 5.46 | $ 5.63 |
| Diluted (in dollars per share) | $ 2.80 | $ 2.98 | $ 5.41 | $ 5.59 |
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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/exampleRef
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- Definition Per basic share amount, after tax, of pro forma income (loss) of combined entity as if acquisition date of business combination occurred as of beginning of period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Per diluted share amount, after tax, of pro forma income (loss) of combined entity as if acquisition date of business combination occurred as of beginning of period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, after tax, of pro forma income (loss) from continuing operations of combined entity as if acquisition date of business combination occurred as of beginning of period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after tax, of pro forma income (loss) of combined entity as if acquisition date of business combination occurred as of beginning of period. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of pro forma revenue of combined entity as if acquisition date of business combination occurred as of beginning of period. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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