Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Financial assets:
Cash and due from banks	$ 27,627	$ 34,096
Interest bearing deposits with financial institutions	45,511	16,536
Securities available-for-sale	449,694	484,648	$ 449,694
FHLBC and FRBC Stock	9,917	9,917
Bank-owned life insurance	61,714	61,763
Financial liabilities:
Noninterest bearing deposits	702,598	669,795
Other short-term borrowings	6,375	48,500
Junior subordinated debentures	25,773	57,734
Reported Value Measurement [Member]
Financial assets:
Cash and due from banks	27,627	34,096
Interest bearing deposits with financial institutions	45,511	16,536
Securities available-for-sale	449,694	484,648
FHLBC and FRBC Stock	9,917	9,917
Loans held for sale	10,049	3,061
Net loans	1,927,159	1,911,023
Interest rate swap agreements	11,115	2,771
Accrued interest receivable	9,392	9,697
Financial liabilities:
Noninterest bearing deposits	702,598	669,795
Interest bearing deposits	1,493,044	1,456,954
Securities sold under repurchase agreements	51,236	48,693
Other short-term borrowings	6,375	48,500
Junior subordinated debentures	25,773	57,734
Senior notes	44,297	44,270
Note payable and other borrowings	26,609	6,673
Interest rate swap	16,795	5,921
Borrowing interest payable	1,728	1,079
Estimate of Fair Value Measurement [Member]
Financial assets:
Cash and due from banks	27,627	34,096
Interest bearing deposits with financial institutions	45,511	16,536
Securities available-for-sale	449,694	484,648
FHLBC and FRBC Stock	9,917	9,917
Loans held for sale	10,049	3,061
Net loans	1,947,974	1,915,531
Interest rate swap agreements	11,115	2,771
Accrued interest receivable	9,392	9,697
Financial liabilities:
Noninterest bearing deposits	702,598	669,975
Interest bearing deposits	1,496,968	1,457,832
Securities sold under repurchase agreements	51,236	48,693
Other short-term borrowings	6,375	48,500
Junior subordinated debentures	9,257	51,188
Senior notes	42,689	46,269
Note payable and other borrowings	27,003	7,003
Interest rate swap	16,795	5,921
Borrowing interest payable	1,728	1,079
Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and due from banks	27,627	34,096
Interest bearing deposits with financial institutions	45,511	16,536
Securities available-for-sale	4,152	4,036
Financial liabilities:
Noninterest bearing deposits	702,598	669,975
Junior subordinated debentures		33,614
Senior notes	42,689	46,269
Borrowing interest payable	4
Fair Value, Inputs, Level 2 [Member]
Financial assets:
Securities available-for-sale	434,385	475,193
FHLBC and FRBC Stock	9,917	9,917
Loans held for sale	10,049	3,061
Interest rate swap agreements	11,115	2,771
Accrued interest receivable	9,392	9,697
Financial liabilities:
Interest bearing deposits	1,496,968	1,457,832
Securities sold under repurchase agreements	51,236	48,693
Other short-term borrowings	6,375	48,500
Junior subordinated debentures	9,257	17,574
Note payable and other borrowings	27,003	7,003
Interest rate swap	16,795	5,921
Borrowing interest payable	1,724	1,079
Level 3
Financial assets:
Securities available-for-sale	11,157	5,419
Net loans	$ 1,947,974	$ 1,915,531

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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The aggregate of all domestic and foreign interest-bearing deposit liabilities.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer.

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Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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