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Acquisitions (Details) - USD ($) |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 26, 2017 | Dec. 31, 2016 | Dec. 31, 2017 | Oct. 28, 2016
Liabilities assumed: |  |  |  |
Goodwill and acquisition costs |  | $ 8,500,000 |  |
Talmer |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Loans payable |  |  |  | $ 223,800,000
Deposits |  |  | $ 48,900,000 | 48,900,000
Assets acquired: |  |  |  |
Cash on hand |  |  |  | 122,000
Loans |  |  |  | 220,988,000
Premises and equipment, net |  |  |  | 230,000
Goodwill |  |  |  | 8,375,000
Core deposit intangible |  |  |  | 659,000
Other assets acquired, including accrued interest, prepaids |  |  |  | 573,000
Liabilities assumed: |  |  |  |
Deposits- noninterest bearing demand |  |  |  | 28,850,000
Deposits- interest bearing - Savings, NOW, Moneymarket |  |  |  | 17,941,000
Deposits - Time |  |  |  | 2,103,000
Other liabilities assumed, including escrow deposits and payables |  |  |  | 574,000
Net assets acquired, or total cash paid for acquisition |  |  |  | $ 181,479,000
Acquisition expenses |  |  | $ 269,000 |
Greater Chicago Financial Corp |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Net cash paid | $ 41,100,000 |  |  |
Subordinated debentures retired | 6,300,000 |  |  |
Total assets | 342,600,000 |  |  |
Debt Conversion, Original Debt, Amount | 2,000,000 |  |  |
Assets acquired: |  |  |  |
Loans | 234,400,000 |  |  |
Liabilities assumed: |  |  |  |
Acquisition expenses | $ 65,000 |  |  |

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- Definition Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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- Definition Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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- Definition Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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- Definition The amount of property, plant, and equipment recognized as of the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=84160947&loc=d3e2207-128464 + Details
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- Definition The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4332-108586 + Details
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