Basis of Presentation and Summary of Significant Accounting Policies (Narrative) (Details) employee in Thousands, $ in Millions	3 Months Ended
Apr. 04, 2025 USD ($) employee	Mar. 29, 2024 USD ($)	Jan. 03, 2025 USD ($)
Significant Accounting Policies [Line Items]
Number of employees in global workforce \| employee	47
Revenue recognized for performance obligation satisfied in the previous periods	$ 27	$ 2
Cash and cash equivalents	842	547	$ 849
Accounts payable and accrued liabilities	2,178		2,131
Cash from operations	58	113
Restricted cash balances	$ 82		141
Adjustment
Significant Accounting Policies [Line Items]
Cash and cash equivalents			94
Accounts payable and accrued liabilities			$ 94
Cash from operations		$ 50
Leidos, Inc.
Significant Accounting Policies [Line Items]
Controlling ownership interest (as percent)	100.00%

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