Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Oct. 01, 2022	Sep. 30, 2023	Oct. 01, 2022
Pay vs Performance Disclosure
Net Income Attributable to Kadant	$ 30,864	$ 27,487	$ 88,673	$ 94,849

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details