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|---|---|---|
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| 0001408075-25-000013-index.html | 2025-05-01 16:31:54 | |
| 0001408075-25-000013.txt | 2025-05-01 16:31:54 | |
 0001408075-25-000013-xbrl.zip | 207176 | 2025-05-01 16:31:54 |
| FilingSummary.xml | 36676 | 2025-05-01 16:31:54 |
| Financial_Report.xlsx | 90987 | 2025-05-01 16:31:54 |
| gpk-20250331.htm | 885851 | 2025-05-01 16:31:54 |
| gpk-20250331.xsd | 44578 | 2025-05-01 16:31:54 |
| gpk-20250331_cal.xml | 62245 | 2025-05-01 16:31:54 |
| gpk-20250331_def.xml | 230711 | 2025-05-01 16:31:54 |
| gpk-20250331_htm.xml | 765775 | 2025-05-01 16:31:54 |
| gpk-20250331_lab.xml | 626674 | 2025-05-01 16:31:54 |
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| gpk03312025ex312.htm | 9625 | 2025-05-01 16:31:54 |
| gpk03312025ex321.htm | 3651 | 2025-05-01 16:31:54 |
| gpk03312025ex322.htm | 3847 | 2025-05-01 16:31:54 |
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| report.css | 2767 | 2025-05-01 16:31:54 |
| Show.js | 1085 | 2025-05-01 16:31:54 |