SUBSEQUENT EVENTS	6 Months Ended
Mar. 28, 2025
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	18. SUBSEQUENT EVENTS On April 30, 2025, Atkore’s Board of Directors declared a quarterly cash dividend of $0.33 per share of common stock payable on May 28, 2025, to stockholders of record on May 16, 2025. On April 30, 2025, Atkore International, Inc., a wholly owned subsidiary of the Company, entered into an amendment of its existing Credit Agreement. See Note 13, “Debt” for additional discussion.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

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