v3.26.1
Transactions With Related Parties - Additional Information (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Related Party Transaction [Line Items]          
Carrying amount of LTP's assets $ 11,015.5 $ 9,041.2 $ 11,015.5 $ 9,041.2 $ 10,725.5
Net sales 2,489.9 2,171.3 $ 4,857.6 4,312.3  
Boise Cascade Co-Owner of LTP          
Related Party Transaction [Line Items]          
Variable interest entity, ownership percentage     50.00%    
Boise Cascade Co-Owner of LTP | Fiber          
Related Party Transaction [Line Items]          
Net sales 21.4 17.9 $ 39.4 32.8  
Boise Cascade Co-Owner of LTP | Wood Products, Including Chips and Logs          
Related Party Transaction [Line Items]          
Fiber costs from related parties 2.8 $ 2.4 $ 5.1 $ 4.0  
Packaging Corporation of America          
Related Party Transaction [Line Items]          
Variable interest entity, ownership percentage     50.00%    
Variable Interest Entity          
Related Party Transaction [Line Items]          
Carrying amount of LTP's assets 5.3   $ 5.3   1.6
Carrying amount of LTP's liabilities $ 5.3   $ 5.3   $ 1.6