v3.26.1
DEBT - Narrative (Details) - USD ($)
6 Months Ended
Sep. 29, 2025
Apr. 30, 2025
Mar. 15, 2023
Mar. 27, 2026
Sep. 30, 2025
May 26, 2021
Senior Secured Term Loan Facility due September 29, 2032 | Secured Debt            
Debt Instrument [Line Items]            
Debt instrument, basis spread on variable rate     2.00%      
Senior Secured Term Loan Facility due September 29, 2032 | Secured Debt | One-month interest period            
Debt Instrument [Line Items]            
Credit spread adjustment     0.11448%      
Senior Secured Term Loan Facility due September 29, 2032 | Secured Debt | Three-month interest period            
Debt Instrument [Line Items]            
Credit spread adjustment     0.26161%      
Senior Secured Term Loan Facility due September 29, 2032 | Secured Debt | Six-month interest period            
Debt Instrument [Line Items]            
Credit spread adjustment     0.42826%      
Senior Term Loan Facility Due September 29, 2032 | Secured Debt            
Debt Instrument [Line Items]            
Debt instrument, extended term, period prior to maturity date 91 days          
Line of credit facility, term, outstanding obligations threshold amount $ 100,000,000          
Debt face amount $ 373,000,000          
Annual amortization rate (as a percent) 1.00%          
Senior Term Loan Facility Due September 29, 2032 | Secured Debt | Term Secured Overnight Financing Rate (SOFR)            
Debt Instrument [Line Items]            
Debt instrument, basis spread on variable rate 2.00%          
Debt instrument, variable rate floor 0.00%          
Senior Term Loan Facility Due September 29, 2032 | Secured Debt | Base Rate            
Debt Instrument [Line Items]            
Debt instrument, basis spread on variable rate 1.00%          
Debt instrument, variable rate floor 1.50%          
Senior Notes due June 2031 | Senior Notes            
Debt Instrument [Line Items]            
Debt face amount           $ 400,000,000
Debt instrument, interest rate, stated percentage           4.25%
Line of credit | ABL Credit Facility            
Debt Instrument [Line Items]            
Credit spread adjustment       0.10%    
Line of credit | ABL Credit Facility | Minimum            
Debt Instrument [Line Items]            
Debt instrument, basis spread on variable rate       1.25%    
Line of credit | ABL Credit Facility | Maximum            
Debt Instrument [Line Items]            
Debt instrument, basis spread on variable rate       1.75%    
Line of credit | ABL Credit Facility | Atkore International            
Debt Instrument [Line Items]            
Credit facility, aggregate commitments       $ 325,000,000    
Credit facility available borrowing capacity       $ 325,000,000 $ 325,000,000  
Line of credit | Amended ABL Credit Facility | Secured Debt            
Debt Instrument [Line Items]            
Debt instrument, extended term, period prior to maturity date   91 days        
Line of credit facility, term, outstanding obligations threshold amount   $ 100,000,000