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Acquisitions (Details) | Apr. 20, 2018 USD ($) item | Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
--- | --- | --- | --- | ---
Business Acquisition [Line Items] |  |  |  |
Acquisition expenses |  | $ 0 | $ 3,500,000 | $ 65,000
Salaries and Employee Benefits |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Acquisition expenses |  |  | 1,100,000 |
Data Processing, Computer and ATM |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Acquisition expenses |  |  | $ 1,800,000 |
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 |  |  |
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 |  |  |
Total liabilities | 289,769,000 |  |  |
Loans payable |  | $ 23,400,000 |  |
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 |  |  |

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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://fasb.org/us-gaap/role/ref/legacyRef -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 deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e31917-109318 + Details
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