Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Paragraph 4
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Amount remaining authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Share Repurchase Plan - Narrative (Details) - USD ($)	Jun. 30, 2026	Mar. 31, 2026	Jan. 21, 2026	Dec. 31, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Subsequent Event [Line Items]
Stock repurchase program, authorized amount	$ 100,000,000	$ 100,000,000			$ 50,000,000	$ 50,000,000
Stock repurchase program, remaining authorized amount	2,822,000	$ 50,379,000		$ 100,000,000	$ 50,000,000	$ 0	$ 0
New S&T Share Repurchase Program
Subsequent Event [Line Items]
Stock repurchase program, authorized amount			$ 100,000,000.0
Stock repurchase program, remaining authorized amount	$ 2,800,000