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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
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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 |  |  |  |  |  |

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- Definition Amount authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 505 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481520/505-30-50-4 + Details
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- Definition Amount remaining authorized for purchase of share under share repurchase plan. Includes, but is not limited to, repurchase of stock and unit of ownership. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 505 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481520/505-30-50-4 + Details
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 830 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481674/830-30-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 855 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483399/855-10-50-2 + Details
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- Details
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