v3.25.4

Income Taxes - Schedule of Cash Paid for Income Taxes, Net of Refunds (Details) - USD ($)	12 Months Ended
	Jan. 02, 2026	Jan. 03, 2025	Dec. 29, 2023
Income Tax Paid, by Individual Jurisdiction [Line Items]
Federal	$ 34,634,000
Foreign	1,989,000
Total cash paid for income taxes, net of refunds	47,995,000	$ 39,723,000	$ 38,944,000
California
Income Tax Paid, by Individual Jurisdiction [Line Items]
State	5,681,000
Massachusetts
Income Tax Paid, by Individual Jurisdiction [Line Items]
State	971,000
Others
Income Tax Paid, by Individual Jurisdiction [Line Items]
State	$ 4,720,000

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.

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Amount, after income tax refund received, of cash paid to federal (national) tax jurisdiction for tax on income.

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Amount, after income tax refund received, of cash paid to foreign tax jurisdiction for tax on income.

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Amount, after income tax refund received, of cash paid to state and local tax jurisdictions for tax on income.

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Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Topic 740
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EXPONENT INC 10-K