Subsequent Event	12 Months Ended
Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventOn January 25, 2021, the Board of Directors authorized a new $25.0 million share repurchase program of the Company’s common stock. Under the new program, 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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