Organization, Operations and Basis of Presentation	6 Months Ended
Jun. 30, 2026
Accounting Policies [Abstract]
Organization, Operations and Basis of Presentation	Organization, Operations and Basis of Presentation Description of Business AdvanSix Inc. ("AdvanSix," the "Company," "we" or "our") is a vertically integrated chemistry company that produces essential materials for diverse end markets. Our value chain of our five U.S.-based manufacturing facilities plays a critical role in global supply chains and enables us to innovate and deliver essential products for our customers across building and construction, fertilizers, agrochemicals, plastics, solvents, packaging, paints, coatings, adhesives, electronics and other end markets. Guided by our core values of Safety, Integrity, Accountability and Respect, AdvanSix strives to deliver best-in-class customer experiences and differentiated products in the industries of nylon solutions, plant nutrients and chemical intermediates. Basis of Presentation The Condensed Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information and with the instructions to Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, the accompanying unaudited Condensed Consolidated Financial Statements contain all adjustments, consisting of only normal recurring adjustments, necessary for a fair statement of the Company's financial position as of June 30, 2026, and its results of operations for the three and six months ended June 30, 2026 and 2025 and cash flows for the six months ended June 30, 2026 and 2025. The year-end Condensed Consolidated Balance Sheet data was derived from audited financial statements but does not include all disclosures required by U.S. GAAP. The results of operations of any interim period are not necessarily indicative of the results of operations to be expected for the full fiscal year. These financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2025. All intercompany transactions have been eliminated. Certain prior period amounts have been reclassified for consistency with the current period presentation. It is our practice to establish actual quarterly closing dates using a predetermined fiscal calendar, which requires our businesses to close their books on a Saturday in order to minimize the potentially disruptive effects of quarterly closing on our business processes. Historically, the effects of this practice have generally not been significant to reported results for any quarter and only existed within a reporting year. In the event that differences in actual closing dates are material to year-over-year comparisons of quarterly or year-to-date results, we will provide the appropriate disclosures. Our actual closing dates for the three and six months ended June 30, 2026 and 2025 were July 4, 2026 and June 28, 2025, respectively, which resulted in six additional reporting days in the six month period from our normal quarterly closing procedures. Liabilities to creditors to whom we have issued checks that remained outstanding at June 30, 2026 and December 31, 2025 aggregated to $3.4 million and $4.9 million, respectively. These were included in Cash and cash equivalents and Accounts payable in the Condensed Consolidated Balance Sheets. As of June 30, 2026, the Company has repurchased a total of 6,391,880 shares of common stock, including 1,146,424 shares withheld to cover tax withholding obligations in connection with the vesting of awards, for an aggregate of $195.5 million at a weighted average market price of $30.58 per share. As of June 30, 2026, approximately $62.0 million remained available for share repurchases under the current authorization approved by the Company's Board of Directors (the "Board") on February 17, 2023. The Company has not repurchased any shares under the currently authorized repurchase program since June 2024. During the period July 1, 2026 through July 31, 2026, no additional shares were repurchased for tax withholding obligations or under the repurchase program. Repurchases may be made from time to time on the open market in accordance with Rule 10b-18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), including through the use of trading plans intended to qualify under Rule 10b5-1 of the Exchange Act. The size and timing of these repurchases will depend on pricing, market and economic conditions, legal and contractual requirements and other factors. The share repurchase program has no expiration date and may be modified, suspended or discontinued at any time. The par value of the shares repurchased is applied to Treasury stock and the excess of the purchase price over par value is applied to Additional paid-in capital.

AdvanSix Inc. ("AdvanSix," the "Company," "we" or "our") is a vertically integrated chemistry company that produces essential materials for diverse end markets. Our value chain of our five U.S.-based manufacturing facilities plays a critical role in global supply chains and enables us to innovate and deliver essential products for our customers across building and construction, fertilizers, agrochemicals, plastics, solvents, packaging, paints, coatings, adhesives, electronics and other end markets. Guided by our core values of Safety, Integrity, Accountability and Respect, AdvanSix strives to deliver best-in-class customer experiences and differentiated products in the industries of nylon solutions, plant nutrients and chemical intermediates.

The Condensed Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information and with the instructions to Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, the accompanying unaudited Condensed Consolidated Financial Statements contain all adjustments, consisting of only normal recurring adjustments, necessary for a fair statement of the Company's financial position as of June 30, 2026, and its results of operations for the three and six months ended June 30, 2026 and 2025 and cash flows for the six months ended June 30, 2026 and 2025. The year-end Condensed Consolidated Balance Sheet data was derived from audited financial statements but does not include all disclosures required by U.S. GAAP. The results of operations of any interim period are not necessarily indicative of the results of operations to be expected for the full fiscal year. These financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2025. All intercompany transactions have been eliminated.

It is our practice to establish actual quarterly closing dates using a predetermined fiscal calendar, which requires our businesses to close their books on a Saturday in order to minimize the potentially disruptive effects of quarterly closing on our business processes. Historically, the effects of this practice have generally not been significant to reported results for any quarter and only existed within a reporting year. In the event that differences in actual closing dates are material to year-over-year comparisons of quarterly or year-to-date results, we will provide the appropriate disclosures. Our actual closing dates for the three and six months ended June 30, 2026 and 2025 were July 4, 2026 and June 28, 2025, respectively, which resulted in six additional reporting days in the six month period from our normal quarterly closing procedures.

Liabilities to creditors to whom we have issued checks that remained outstanding at June 30, 2026 and December 31, 2025 aggregated to $3.4 million and $4.9 million, respectively. These were included in Cash and cash equivalents and Accounts payable in the Condensed Consolidated Balance Sheets.

As of June 30, 2026, the Company has repurchased a total of 6,391,880 shares of common stock, including 1,146,424 shares withheld to cover tax withholding obligations in connection with the vesting of awards, for an aggregate of $195.5 million at a weighted average market price of $30.58 per share. As of June 30, 2026, approximately $62.0 million remained available for share repurchases under the current authorization approved by the Company's Board of Directors (the "Board") on February 17, 2023. The Company has not repurchased any shares under the currently authorized repurchase program since June 2024. During the period July 1, 2026 through July 31, 2026, no additional shares were repurchased for tax withholding obligations or under the repurchase program.

Repurchases may be made from time to time on the open market in accordance with Rule 10b-18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), including through the use of trading plans intended to qualify under Rule 10b5-1 of the Exchange Act. The size and timing of these repurchases will depend on pricing, market and economic conditions, legal and contractual requirements and other factors. The share repurchase program has no expiration date and may be modified, suspended or discontinued at any time. The par value of the shares repurchased is applied to Treasury stock and the excess of the purchase price over par value is applied to Additional paid-in capital.