OTHER INCOME (EXPENSE)	6 Months Ended
Mar. 31, 2026
Other Income and Expenses [Abstract]
OTHER INCOME (EXPENSE)	OTHER INCOME (EXPENSE) For the quarters ended March 31, 2026 and 2025, Other income (expense) of $(1,238) and $317, respectively, includes $134 and ($6), respectively, of net currency exchange gains (losses) in connection with the translation of receivables and payables denominated in currencies other than the functional currencies of Griffon and its subsidiaries, net periodic benefit plan expense of $(1,908) and $(40), respectively, net gains (losses) on investments of $122 and $(16), respectively, and royalty income of $445 and $556, respectively. Net periodic benefit plan expense includes a charge of $1,609 recorded in the three months ended March 31, 2026 associated with the establishment of a new retiree medical plan. Refer to Note 13 - Employee Benefit Plans for additional details. For the six months ended March 31, 2026 and 2025, Other income (expense) of $(2,616) and $586, respectively, includes $283 and $(276), respectively, of net currency exchange gains (losses) in connection with the translation of receivables and payables denominated in currencies other than the functional currencies of Griffon and its subsidiaries, net periodic benefit plan expense of $(3,815) and $(81), respectively, net gains (losses) on investments of $(7) and $54, respectively, and royalty income of $964 and $1,146, respectively. Net periodic benefit plan expense includes a charge of $3,218 recorded in the six months ended March 31, 2026 associated with the establishment of a new retiree medical plan. Refer to Note 13 - Employee Benefit Plans for additional details.

For the quarters ended March 31, 2026 and 2025, Other income (expense) of $(1,238) and $317, respectively, includes $134 and ($6), respectively, of net currency exchange gains (losses) in connection with the translation of receivables and payables denominated in currencies other than the functional currencies of Griffon and its subsidiaries, net periodic benefit plan expense of $(1,908) and $(40), respectively, net gains (losses) on investments of $122 and $(16), respectively, and royalty income of $445 and $556, respectively. Net periodic benefit plan expense includes a charge of $1,609 recorded in the three months ended March 31, 2026 associated with the establishment of a new retiree medical plan. Refer to Note 13 - Employee Benefit Plans for additional details.

For the six months ended March 31, 2026 and 2025, Other income (expense) of $(2,616) and $586, respectively, includes $283 and $(276), respectively, of net currency exchange gains (losses) in connection with the translation of receivables and payables denominated in currencies other than the functional currencies of Griffon and its subsidiaries, net periodic benefit plan expense of $(3,815) and $(81), respectively, net gains (losses) on investments of $(7) and $54, respectively, and royalty income of $964 and $1,146, respectively. Net periodic benefit plan expense includes a charge of $3,218 recorded in the six months ended March 31, 2026 associated with the establishment of a new retiree medical plan. Refer to Note 13 - Employee Benefit Plans for additional details.