Subsequent Events	3 Months Ended
Apr. 05, 2026
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On May 6, 2026, the Board declared a cash dividend of $0.085 per share. The dividend is payable on June 4, 2026 to all shareholders of record as of the close of business on May 21, 2026. Additionally, on April 29, 2026, the shareholders of the Company approved an amendment to the Cognex Corporation 2023 Stock Option and Incentive Plan (the “2023 Plan”) to increase the maximum amount of shares of common stock available to be issued under the plan by 4,600,000 shares.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

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