Condensed Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 30, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net Income	$ 11,065	$ 11,008
Other Comprehensive Items:
Foreign currency translation adjustment	(465)	5,336
Pension and other post-retirement liability adjustments (net of tax provision of $8 and $34)	21	117
Deferred (loss) gain on cash flow hedges (net of tax benefit (provision) of $104 and ($8))	(237)	93
Other Comprehensive Items	(681)	5,546
Comprehensive Income	10,384	16,554
Comprehensive Income Attributable to Noncontrolling Interest	(132)	(193)
Comprehensive Income Attributable to Kadant	$ 10,252	$ 16,361

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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