Fair Values of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended	12 Months Ended
Apr. 30, 2015	Dec. 31, 2014	Mar. 31, 2015
Fair Values of Financial Instruments
FHLBC Redemptions	$ 788	$ 1,200
Financial assets:
Cash and due from banks		30,101us-gaap_CashAndDueFromBanks	19,051us-gaap_CashAndDueFromBanks
Interest bearing deposits with financial institutions		14,096us-gaap_InterestBearingDepositsInBanks	55,111us-gaap_InterestBearingDepositsInBanks
Securities available-for-sale		385,486us-gaap_AvailableForSaleSecurities	399,252us-gaap_AvailableForSaleSecurities
Securities held-to-maturity		259,670	257,332
FHLBC and Reserve Bank Stock		9,058	9,058
Bank-owned life insurance		56,807us-gaap_BankOwnedLifeInsurance	57,161us-gaap_BankOwnedLifeInsurance
Financial liabilities:
Noninterest bearing deposits		400,447	431,843
Other short-term borrowings		45,000us-gaap_OtherShortTermBorrowings	30,000us-gaap_OtherShortTermBorrowings
Junior subordinated debentures		58,378	58,378
Level 1
Financial assets:
Cash and due from banks		30,101	19,051
Interest bearing deposits with financial institutions		14,096	55,111
Securities available-for-sale		1,527	1,525
Financial liabilities:
Noninterest bearing deposits		400,447	431,843
Junior subordinated debentures		32,441	32,408
Level 2
Financial assets:
Securities available-for-sale		330,900	397,609
Securities held-to-maturity		263,266	265,095
FHLBC and Reserve Bank Stock		9,058	9,058
Bank-owned life insurance		56,807	57,161
Loans held for sale		5,072	7,038
Accrued interest receivable		4,888	4,953
Financial liabilities:
Interest bearing deposits		1,284,887	1,313,710
Securities sold under repurchase agreements		21,036	26,513
Other short-term borrowings		45,000	30,000
Junior subordinated debentures		22,245	22,223
Subordinated debenture		39,366	39,690
Note payable and other borrowings		422	427
Borrowing interest payable		75	68
Deposit interest payable		467	421
Level 3
Financial assets:
Securities available-for-sale		53,059	118
Loans, net		1,151,223	1,142,727
Carrying Amount
Financial assets:
Cash and due from banks		30,101	19,051
Interest bearing deposits with financial institutions		14,096	55,111
Securities available-for-sale		385,486	399,252
Securities held-to-maturity		259,670	257,332
FHLBC and Reserve Bank Stock		9,058	9,058
Bank-owned life insurance		56,807	57,161
Loans held for sale		5,072	7,038
Loans, net		1,137,695	1,129,888
Accrued interest receivable		4,888	4,953
Financial liabilities:
Noninterest bearing deposits		400,447	431,843
Interest bearing deposits		1,284,608	1,312,935
Securities sold under repurchase agreements		21,036	26,513
Other short-term borrowings		45,000	30,000
Junior subordinated debentures		58,378	58,378
Subordinated debenture		45,000	45,000
Note payable and other borrowings		500	500
Borrowing interest payable		75	68
Deposit interest payable		467	421
Total
Financial assets:
Cash and due from banks		30,101	19,051
Interest bearing deposits with financial institutions		14,096	55,111
Securities available-for-sale		385,486	399,252
Securities held-to-maturity		263,266	265,095
FHLBC and Reserve Bank Stock		9,058	9,058
Bank-owned life insurance		56,807	57,161
Loans held for sale		5,072	7,038
Loans, net		1,151,223	1,142,727
Accrued interest receivable		4,888	4,953
Financial liabilities:
Noninterest bearing deposits		400,447	431,843
Interest bearing deposits		1,284,887	1,313,710
Securities sold under repurchase agreements		21,036	26,513
Other short-term borrowings		45,000	30,000
Junior subordinated debentures		54,686	54,631
Subordinated debenture		39,366	39,690
Note payable and other borrowings		422	427
Borrowing interest payable		75	68
Deposit interest payable		$ 467	$ 421

Represents the fair value of interest payable related to deposits at the balance sheet date.

No definition available.

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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 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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No definition available.

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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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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Amount of interest payable on debt, including, but not limited to, trade payables.

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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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Sum of the carrying amounts at the balance sheet date of short-term borrowings not otherwise specified in the taxonomy having initial terms less than one year or the normal operating cycle, if longer.

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Amount of cash inflow from sale of Federal Home Loan Bank (FHLB) stock.

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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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