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Branch Sale (Details) - USD ($) $ in Thousands	Apr. 26, 2019	Sep. 30, 2019	Dec. 31, 2018
Branch Sale
Loans and Leases Receivable, Net Amount		$ 1,663,103	$ 1,679,676
Deposits		$ 1,833,113	$ 1,775,096
Disposed of by Sale \| Branch Offices in Duluth, MN
Branch Sale
Loans and Leases Receivable, Net Amount	$ 28,300
Deposits	19,400
Pre-tax gain on sale of branch	$ 1,500