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Acquisitions (Details) |  | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Apr. 20, 2018 USD ($) item | Dec. 31, 2018 USD ($) | Dec. 26, 2017 USD ($) | Dec. 31, 2016 USD ($) | Oct. 28, 2016 USD ($) | Oct. 26, 2016 USD ($)
GCFC/ABC Bank |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Number of bank branches operated | item | 4 |  |  |  |  |
Acquisition price | $ 41,100,000 |  |  |  |  |
Net cash paid | 47,180,000 |  |  |  |  |
Subordinated debentures retired | 6,600,000 | $ 304,800,000 |  |  |  |
Goodwill |  | 10,200,000 |  |  |  |
Core deposit intangible |  | 3,100,000 |  |  |  |
Valuation adjustment, fixed assets |  | 1,500,000 |  |  |  |
Valuation adjustment, loan valuation mark |  | 11,200,000 |  |  |  |
Acquisition expenses |  |  | $ 65,000 |  |  |
Total liabilities | 289,769,000 |  |  |  |  |
Loans payable |  | 23,400,000 |  |  |  |
Deposits |  | 248,500,000 |  |  |  |
Assets acquired: |  |  |  |  |  |
Cash on due from banks | 6,669,000 |  |  |  |  |
Interest bearing deposits with financial institutions | 500,000 |  |  |  |  |
Securities available-for-sale, at fair value | 72,091,000 |  |  |  |  |
Federal funds sold | 4,300,000 |  |  |  |  |
FHLBC stock | 1,549,000 |  |  |  |  |
Loans | 227,594,000 |  |  |  |  |
Premises and equipment | 5,339,000 |  |  |  |  |
Other real estate owned | 401,000 |  |  |  |  |
Goodwill and core deposit intangible | 13,280,000 |  |  |  |  |
Deferred tax assets, net | 3,459,000 |  |  |  |  |
Other assets | 1,767,000 |  |  |  |  |
Total assets | 336,949,000 |  |  |  |  |
Liabilities assumed: |  |  |  |  |  |
Deposits-noninterest bearing demand | 58,005,000 |  |  |  |  |
Deposits - Savings, NOW and money market | 91,494,000 |  |  |  |  |
Deposits-Time | 98,999,000 |  |  |  |  |
Total deposits | 248,498,000 |  |  |  |  |
Securities sold under repurchase agreements | 5,623,000 |  |  |  |  |
Other short-term borrowings | 10,875,000 |  |  |  |  |
Notes payable and other borrowings | 23,367,000 |  |  |  |  |
Other liabilities | 1,406,000 |  |  |  |  |
Total liabilities | 289,769,000 |  |  |  |  |
Cash consideration paid | 47,180,000 |  |  |  |  |
Total Liabilities Assumed and Cash Consideration Paid for Acquisition | $ 336,949,000 |  |  |  |  |
GCFC/ABC Bank | Selling, General and Administrative Expenses [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Acquisition expenses |  | 3,500,000 |  |  |  |
GCFC/ABC Bank | Salaries and Employee Benefits |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Acquisition expenses |  | 1,100,000 |  |  |  |
GCFC/ABC Bank | Data Processing, Computer and ATM |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Acquisition expenses |  | $ 1,800,000 |  |  |  |
Talmer |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Acquisition expenses |  |  |  | $ 269,000 |  |
Loans payable |  |  |  |  | $ 221,000,000 |
Deposits |  |  |  |  | $ 48,900,000 |
Liabilities assumed: |  |  |  |  |  |
Total Liabilities Assumed and Cash Consideration Paid for Acquisition |  |  |  |  |  | $ 181,500,000

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