Business Acquisition, Pro Forma Earnings Per Share [Abstract]

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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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Acquisitions - 2021 Acquisition Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 30, 2023	Dec. 31, 2022	Jan. 01, 2022
Earnings per Share Attributable to Kadant
Cost of revenue	$ 541,366	$ 515,184	$ 449,214
Selling, general, and administrative expenses	$ 236,264	$ 224,405	208,787
Clouth
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenue			812,016
Net Income Attributable to Kadant			$ 90,184
Earnings per Share Attributable to Kadant
Basic (in dollars per share)			$ 7.79
Diluted (in dollars per share)			$ 7.74
Clouth \| Inventory revalued
Earnings per Share Attributable to Kadant
Cost of revenue			$ 3,082
Clouth \| Acquisition-related Costs
Earnings per Share Attributable to Kadant
Selling, general, and administrative expenses			2,710
Amortization			$ 399