Subordinated Debentures Subordinated Debentures, Additional Information (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Debt Instrument [Line Items] | ||||
| Amortization of Debt Discount (Premium) | $ 806 | $ 0 | $ 806 | $ 0 |
| First Commonwealth Capital Trust II [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Debt Issuance Costs, Gross | 500 | 500 | ||
| First Commonwealth Bank 2033 [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Subordinated Debt Par Amount | 50,000 | 50,000 | ||
| Debt Issuance Costs, Gross | 1,100 | 1,100 | ||
| First Commonwealth Capital Trust III [Member] | ||||
| Debt Instrument [Line Items] | ||||
| Debt Issuance Costs, Gross | 600 | 600 | ||
| First Commonwealth Financial Corporation | ||||
| Debt Instrument [Line Items] | ||||
| Subordinated Debt Par Amount | $ 6,000 | $ 6,000 | ||
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- Definition Subordinated Debt Par Amount No definition available.
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- Definition Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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