Condensed Consolidated Statement of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net Income	$ 16,401	$ 12,491	$ 27,466	$ 23,499
Other Comprehensive Items:
Foreign currency translation adjustment	1,953	(15,776)	1,488	(10,440)
Pension and other post-retirement liability adjustments (net of tax provision of $2, $75, $10 and $109)	7	212	28	329
Deferred loss on cash flow hedges (net of tax benefit of $39, $55, $143 and $47)	(164)	(173)	(401)	(80)
Other Comprehensive Items	1,796	(15,737)	1,115	(10,191)
Comprehensive Income (Loss)	18,197	(3,246)	28,581	13,308
Comprehensive Income Attributable to Noncontrolling Interest	(120)	(46)	(252)	(239)
Comprehensive Income (Loss) Attributable to Kadant	$ 18,077	$ (3,292)	$ 28,329	$ 13,069

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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