v3.25.3

Business Combinations and Asset Acquisitions (Details) - USD ($) $ in Thousands		9 Months Ended
	May 01, 2025	Sep. 30, 2025
Business Combination [Line Items]
Business Combination, Consideration Transferred		$ 46,206
Business Combination, Recognized Asset Acquired, Asset, Current	$ 4,672
Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent	336,164
Business Combination, Recognized Liability Assumed, Long-Term Debt, Noncurrent	22,785
Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent	3,692
Business Combination, Recognized Liability Assumed, Liability	304,457
Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less)	31,707
Goodwill, Acquired During Period	14,499
Business Combination, Recognized Asset Acquired, Investment in Debt and Equity Securities, Current	21,396
Business Combination, Recognized Asset Acquired, Receivable, Current	291,852
Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment, Land	4,276
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill	5,355
Asset Acquisition, Consideration Transferred, Equity Interest Issued and Issuable	46,205
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, FHLB Stock	3,144
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Bank Owned Life Insurance	430
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Assets	5,039
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed, Deposits Contractual Amount	277,980
Payments to Acquire Businesses, Gross	$ 1
CenterBank
Business Combination [Line Items]
Business Combination, Consideration Transferred, Equity Interest, Share Issued, Number of Shares	3,016,009

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FIRST COMMONWEALTH FINANCIAL CORP /PA/ 10-Q