Quarterly report pursuant to Section 13 or 15(d)

Nature of Operations - Additional Information (Detail)

v3.22.1
Nature of Operations - Additional Information (Detail)
3 Months Ended 9 Months Ended
Jun. 26, 2021
Sep. 25, 2021
USD ($)
Sep. 25, 2020
USD ($)
Sep. 25, 2021
USD ($)
Segments
Sep. 25, 2020
USD ($)
Aug. 31, 2021
Aug. 18, 2021
Jan. 18, 2021
Dec. 26, 2020
USD ($)
Jan. 02, 2020
Schedule of Equity Method Investments [Line Items]                    
Business Combination Percentage of Net Assets Acquired               100.00%    
Number of reportable segments 2     2            
Assets   $ 1,130,374,999   $ 1,130,374,999         $ 873,478,745  
Revenue   187,789,925 $ 140,339,058 514,796,582 $ 400,382,475          
Access Control Technologies, LLC                    
Schedule of Equity Method Investments [Line Items]                    
Business Acquisition, Percentage of Voting Interests Acquired           100.00%        
DBCI, LLC                    
Schedule of Equity Method Investments [Line Items]                    
Business Acquisition, Percentage of Voting Interests Acquired             100.00%      
Foreign Locations [Member]                    
Schedule of Equity Method Investments [Line Items]                    
Assets   56,439,000   56,439,000         $ 53,424,000  
Revenue   $ 17,824,000 $ 12,621,000 $ 48,729,000 $ 32,165,000          
Janus International Europe Holdings Ltd UK JIE [Member]                    
Schedule of Equity Method Investments [Line Items]                    
Equity Method Investment, Ownership Percentage   100.00%   100.00%            
Janus International Europe Holdings Ltd UK JIE [Member] | Active Supply Design CDM Ltd UKASD [Member]                    
Schedule of Equity Method Investments [Line Items]                    
Equity Method Investment, Ownership Percentage   100.00%   100.00%            
Janus International Europe Holdings Ltd UK JIE [Member] | Steel Storage Australia Asia Steel Storage [Member]                    
Schedule of Equity Method Investments [Line Items]                    
Equity Method Investment, Ownership Percentage   100.00%   100.00%            
Percentage Of Outstanding Shares Purchased                   100.00%
Janus Cob bHoldings LLC Cobb [Member] | Asta Industries Inc ASTA [Member]                    
Schedule of Equity Method Investments [Line Items]                    
Equity Method Investment, Ownership Percentage   100.00%   100.00%            
Janus Cob bHoldings LLC Cobb [Member] | Nok Inc NOKE [Member]                    
Schedule of Equity Method Investments [Line Items]                    
Equity Method Investment, Ownership Percentage   100.00%   100.00%