v3.25.2
Segment Information - Selected Financial Information by Reportable Segment (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Segment Reporting Information [Line Items]          
Net sales $ 2,171.3 $ 2,075.3 $ 4,312.3 $ 4,054.8  
Operating Income (Loss) [1] 333.7 276.0 614.0 472.0  
Other segment items [1],[2] 0.0 0.0 0.0 0.0  
Non-operating pension expense 0.0 1.1 0.0 2.2  
Interest expense, net (13.1) (10.4) (26.0) (19.9)  
Income before taxes 320.6 266.7 588.0 454.3  
Depreciation, amortization, and depletion 140.7 128.5 278.6 256.9  
Capital expenditures [3] 169.7 245.0 317.8 321.7  
Assets 9,041.2 8,982.1 9,041.2 8,982.1 $ 8,833.2
Variable Costs [Member]          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1],[4] 0.0 0.0 0.0 0.0  
Fixed Costs [Member]          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1],[5] 0.0 0.0 0.0 0.0  
Freight          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1] 0.0 0.0 0.0 0.0  
Operating Segments          
Segment Reporting Information [Line Items]          
Net sales 2,210.1 2,120.4 4,391.1 4,144.1  
Operating Segments | Trade          
Segment Reporting Information [Line Items]          
Net sales 2,171.3 2,075.3 4,312.3 4,054.8  
Operating Segments | Intersegment          
Segment Reporting Information [Line Items]          
Net sales 38.8 45.1 78.8 89.3  
Elimination of intersegment sales          
Segment Reporting Information [Line Items]          
Net sales (38.8) (45.1) (78.8) (89.3)  
Packaging          
Segment Reporting Information [Line Items]          
Net sales 2,005.9 1,908.3 3,976.3 3,706.5  
Operating Income (Loss) [1] 346.3 279.8 624.4 483.6  
Other segment items [1],[2] (55.9) (77.5) (142.9) (142.0)  
Depreciation, amortization, and depletion 131.8 120.1 260.1 238.6  
Capital expenditures [3] 165.0 231.9 296.1 303.6  
Assets 7,418.6 7,102.6 7,418.6 7,102.6  
Packaging | Variable Costs [Member]          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1],[4] (960.1) (937.1) (1,921.2) (1,874.9)  
Packaging | Fixed Costs [Member]          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1],[5] (445.2) (412.9) (892.7) (817.9)  
Packaging | Trade          
Segment Reporting Information [Line Items]          
Net sales 2,005.9 1,902.0 3,976.3 3,695.4  
Packaging | Intersegment          
Segment Reporting Information [Line Items]          
Net sales 0.0 6.3 0.0 11.1  
Packaging | Freight          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1] (198.4) (201.0) (395.1) (388.1)  
Packaging | Operating Segments          
Segment Reporting Information [Line Items]          
Net sales 2,005.9 1,908.3 3,976.3 3,706.5  
Paper          
Segment Reporting Information [Line Items]          
Net sales 145.8 150.1 300.0 313.9  
Operating Income (Loss) [1] 25.8 26.7 61.4 56.4  
Other segment items [1],[2] (0.2) 0.0 (0.3) (5.2)  
Depreciation, amortization, and depletion 4.5 4.5 9.1 10.5  
Capital expenditures [3] 1.0 2.6 1.8 3.9  
Assets 405.3 383.6 405.3 383.6  
Paper | Variable Costs [Member]          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1],[4] (82.8) (84.1) (165.7) (173.5)  
Paper | Fixed Costs [Member]          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1],[5] (21.8) (22.0) (40.6) (43.5)  
Paper | Trade          
Segment Reporting Information [Line Items]          
Net sales 145.8 150.1 300.0 313.9  
Paper | Intersegment          
Segment Reporting Information [Line Items]          
Net sales 0.0 0.0 0.0 0.0  
Paper | Freight          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1] (15.2) (17.3) (32.0) (35.3)  
Paper | Operating Segments          
Segment Reporting Information [Line Items]          
Net sales 145.8 150.1 300.0 313.9  
Corporate and Other          
Segment Reporting Information [Line Items]          
Net sales 19.6 16.9 36.0 [6] 34.4  
Operating Income (Loss) [1] (38.4) (30.5) [7] (71.8) [7] (68.0) [7]  
Other segment items [1],[2] (96.8) (92.5) (186.6) (191.7)  
Depreciation, amortization, and depletion 4.4 3.9 9.4 7.8  
Capital expenditures [3] 3.7 10.5 19.9 14.2  
Assets 1,217.3 1,495.9 1,217.3 1,495.9  
Corporate and Other | Variable Costs [Member]          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1],[4] 0.0 0.0 0.0 0.0  
Corporate and Other | Fixed Costs [Member]          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1],[5] 0.0 0.0 0.0 0.0  
Corporate and Other | Trade          
Segment Reporting Information [Line Items]          
Net sales 19.6 23.2 [6] 36.0 45.5 [6]  
Corporate and Other | Intersegment          
Segment Reporting Information [Line Items]          
Net sales 38.8 38.8 78.8 78.2  
Corporate and Other | Freight          
Segment Reporting Information [Line Items]          
Operating Income (Loss) [1] 0.0 0.0 0.0 0.0  
Corporate and Other | Operating Segments          
Segment Reporting Information [Line Items]          
Net sales $ 58.4 $ 62.0 $ 114.8 $ 123.7  
[1] The significant expense categories align with the segment-level information that is regularly provided to the CODM.
[2] Other segment items for each reportable segment primarily include:
1.
Packaging: farmout purchases, certain divisional allocations, and other expense/income items.
2.
Paper: other expense/income items.
3.
Corporate and Other: unallocated corporate costs, transportation business activity, and activity related to LTP.
[3] Includes “Additions to property, plant, and equipment” and excludes cash used for “Acquisition of business, net of cash acquired” as reported on our Consolidated Statements of Cash Flows.
[4] For the Packaging segment, primarily includes expense items for liner consumption, liner board discount, purchased sheets usage, medium consumption, raw materials, and hourly-employee related expenses and benefits. For the Paper segment, primarily includes expense items for chemicals, raw materials, finishing materials, and hourly-employee related expenses and benefits.
[5] For the Packaging segment, primarily includes expense items for depreciation and salaried employee-related expenses and benefits. For the Paper segment, primarily includes expense items for depreciation, salaried employee-related expenses, and professional services.
[6] The Corporate and Other segment sales to external customers is presented net of total company intersegment eliminations.
[7] The significant expense categories reported for the Packaging and Paper segments are not used for Corporate and Other in the segment-level information that is regularly reviewed by the CODM. The CODM makes resource allocation decisions for Corporate and Other based on divisional income (loss) from operations.