Represents the geographical area from lending offices which attempt is made to lend short and intermediate term loans.

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Represents the threshold amount of borrowing above which the Board of Directors reviews relationships annually.

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Represents the maximum limit of total borrowing relationships (direct and indirect).

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Represents the entity's maximum target period for lending via intermediate term loans and leases receivable.

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No definition available.

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Represents the entity's minimum target period for lending via intermediate term loans and leases receivable.

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Represents the primary area in which the loans are segregated.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount classified as loans attributable to disposal group held for sale or disposed of. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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Loans (Details) $ in Thousands	9 Months Ended
Loans (Details) $ in Thousands	Sep. 30, 2015 USD ($) item mi	Jun. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2013 USD ($)
Loans
Total	$ 2,581,014		$ 2,415,690
Less held for sale	15,694		10,400
Total loans before allowance for loan losses	2,565,320		2,405,290
Less allowance for loan losses	47,212		47,453
Net loans	2,518,108		2,357,837
Net deferred loan origination costs	$ 800		600
Minimum target period for lending via intermediate term loans	0 years
Maximum target period for lending via intermediate term loans	7 years
Geographical area from lending offices which attempt is made to lend short and intermediate term loans (in miles) \| mi	125
Direct and indirect maximum total borrowing relationship limit	$ 20,000
Borrowing relationships, threshold above which board of directors will review annually	$ 20,000
Number of primary areas for lending loan \| item	5
Illinois
Loans
Total	$ 2,062,584		1,909,668
Florida
Loans
Total	309,883		313,152
Total loans before allowance for loan losses	309,441		312,528
Less allowance for loan losses	6,721	$ 7,461	8,511	$ 9,708	$ 10,491	$ 13,118
Indiana
Loans
Total	208,547		192,870
Commercial
Loans
Total	621,295		601,760
Commercial \| Illinois
Loans
Total	574,073		554,779
Commercial \| Florida
Loans
Total	17,001		16,739
Total loans before allowance for loan losses	17,001		16,739
Less allowance for loan losses	761	724	1,172	1,255	1,782	1,926
Commercial \| Indiana
Loans
Total	30,221		30,242
Commercial real estate
Loans
Total	1,184,690		1,104,151
Commercial real estate \| Illinois
Loans
Total	881,925		811,034
Commercial real estate \| Florida
Loans
Total	171,686		171,243
Total loans before allowance for loan losses	171,686		171,243
Less allowance for loan losses	3,393	4,007	4,205	5,092	4,976	5,733
Commercial real estate \| Indiana
Loans
Total	131,079		121,874
Real estate construction
Loans
Total	103,868		107,054
Real estate construction \| Illinois
Loans
Total	53,869		60,994
Real estate construction \| Florida
Loans
Total	14,472		17,950
Total loans before allowance for loan losses	14,472		17,950
Less allowance for loan losses	174	167	205	180	175	1,168
Real estate construction \| Indiana
Loans
Total	35,527		28,110
Retail real estate
Loans
Total	654,774		592,473
Retail real estate \| Illinois
Loans
Total	537,283		473,171
Retail real estate \| Florida
Loans
Total	105,771		106,658
Total loans before allowance for loan losses	105,329		106,034
Less allowance for loan losses	2,376	2,550	2,917	3,169	3,554	4,287
Retail real estate \| Indiana
Loans
Total	11,720		12,644
Retail other
Loans
Total	16,387		10,252
Retail other \| Illinois
Loans
Total	15,434		9,690
Retail other \| Florida
Loans
Total	953		562
Total loans before allowance for loan losses	953		562
Less allowance for loan losses	$ 17	$ 13	$ 12	$ 12	$ 4	$ 4