Condensed Consolidated Statement of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2024	Sep. 30, 2023	Sep. 28, 2024	Sep. 30, 2023
Income Statement [Abstract]
Revenue (Notes 1 and 11)	$ 271,614	$ 244,182	$ 795,354	$ 718,993
Costs and Operating Expenses:
Cost of revenue	150,175	138,456	441,066	404,671
Selling, general, and administrative expenses	69,043	57,889	209,352	176,441
Research and development expenses	3,409	3,324	10,621	10,102
Other costs (Note 3)	0	969	0	1,043
Total Costs and Operating Expenses	222,627	200,638	661,039	592,257
Operating Income	48,987	43,544	134,315	126,736
Interest Income	407	438	1,386	1,053
Interest Expense	(5,516)	(2,107)	(15,386)	(6,722)
Other Expense, Net	(16)	(20)	(48)	(62)
Income Before Provision for Income Taxes	43,862	41,855	120,267	121,005
Provision for Income Taxes (Note 5)	11,964	10,816	31,810	31,761
Net Income	31,898	31,039	88,457	89,244
Net Income Attributable to Noncontrolling Interests	(312)	(175)	(891)	(571)
Net Income Attributable to Kadant	$ 31,586	$ 30,864	$ 87,566	$ 88,673
Earnings per Share Attributable to Kadant (Note 4)
Basic (in dollars per share)	$ 2.69	$ 2.64	$ 7.46	$ 7.58
Diluted (in dollars per share)	$ 2.68	$ 2.63	$ 7.44	$ 7.57
Weighted Average Shares (Note 4)
Basic (in shares)	11,745	11,706	11,737	11,697
Diluted (in shares)	11,780	11,740	11,763	11,719