Cash and Due from Banks	12 Months Ended
	Dec. 31, 2022
Cash and Due from Banks [Abstract]
Cash and Due from Banks	Cash and Due from BanksRegulations of the Board of Governors of the Federal Reserve System impose uniform reserve requirements on all depository institutions with transaction accounts, such as checking accounts and NOW accounts. Reserves are maintained in the form of vault cash or balances held with the local Federal Reserve Bank. Because balances held at the Federal Reserve earn interest, depending on our liquidity position, we may maintain balances in excess of the reserve requirement. First Commonwealth maintained average balances of $181.6 million during 2022 and $309.6 million during 2021 with the Federal Reserve Bank of Cleveland.