Subsequent Events	3 Months Ended
Mar. 31, 2023
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventOn April 24, 2023, the Board of Directors authorized an increase of $25.0 million to the existing share repurchase program of the Company's common stock. Management is authorized to repurchase shares through Rule 10b5-1 plans, open market purchases, privately negotiated transactions, block purchases or otherwise in a manner that is intended to comply with applicable federal securities laws, including Rule 10b-18 of the Securities Exchange Act of 1934. First Commonwealth may suspend or discontinue the program at any time.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

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