Earnings per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 28, 2014	Jun. 29, 2013	Jun. 28, 2014	Jun. 29, 2013
Amounts Attributable to Kadant [Abstract]
Income from Continuing Operations	$ 7,867	$ 5,772	$ 12,925	$ 11,085
Loss from Discontinued Operation	(9)	(12)	(14)	(41)
Net Income Attributable to Kadant	$ 7,858	$ 5,760	$ 12,911	$ 11,044
Basic Weighted Average Shares (in shares)	11,049,000	11,178,000	11,091,000	11,170,000
Effect of Stock Options, Restricted Stock Units and Employee Stock Purchase Plan (in shares)	197,000	153,000	189,000	129,000
Diluted Weighted Average Shares (in shares)	11,246,000	11,331,000	11,280,000	11,299,000
Basic Earnings Per Share [Abstract]
Continuing operations (in dollars per share)	$ 0.71	$ 0.52	$ 1.17	$ 0.99
Discontinued operation (in dollars per share)	$ 0.00	$ 0.00	$ 0.00	$ 0.00
Net Income per Basic Share (in dollars per share)	$ 0.71	$ 0.52	$ 1.16	$ 0.99
Diluted Earnings Per Share [Abstract]
Continuing operations (in dollars per share)	$ 0.70	$ 0.51	$ 1.15	$ 0.98
Discontinued operation (in dollars per share)	$ 0.00	$ 0.00	$ 0.00	$ 0.00
Net Income per Diluted Share (in dollars per share)	$ 0.70	$ 0.51	$ 1.14	$ 0.98
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)		93,000		102,000
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	69,000	0	63,000	41,000