Janus International Group Quarterly report [Sections 13 or 15(d)]

Quarterly report [Sections 13 or 15(d)]

Cover
- Cover Page
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Summary of Significant Accounting Policies - Narrative (Details)

v3.26.3

Summary of Significant Accounting Policies - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 03, 2026 USD ($)	Sep. 27, 2025 USD ($)	Oct. 03, 2026 USD ($) segment	Sep. 27, 2025 USD ($)
Schedule of Equity Method Investments [Line Items]
Interest income	$ 0.8	$ 1.6	$ 2.4	$ 3.9
Product warranty obligation, term	10 years		10 years
Number of reportable segments \| segment			2
Number of operating segments \| segment			2
Governmental grants as a reduction			$ 4.0
IEEPA Tariff Refund
Schedule of Equity Method Investments [Line Items]
Recovery of tariff refunds			$ 1.6
Customer One \| Inventory Concentration Risk \| Customer Concentration Risk
Schedule of Equity Method Investments [Line Items]
Concentration percentage	14.00%
Minimum
Schedule of Equity Method Investments [Line Items]
Product warranty obligation, term	1 year		1 year
Maximum
Schedule of Equity Method Investments [Line Items]
Product warranty obligation, term	3 years		3 years
Transferred at Point in Time
Schedule of Equity Method Investments [Line Items]
Percentage of revenue transferred	61.00%	66.00%	59.00%	67.00%
Service revenues transferred over time
Schedule of Equity Method Investments [Line Items]
Percentage of revenue transferred	39.00%	34.00%	41.00%	33.00%

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