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Mergers and Acquisitions (Details Textual) - USD ($) | 3 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Business Acquisition |  |
Effective settlement of a pre-existing relationship | $ 10,054,000 | $ 0
First Security Bank |  |
Business Acquisition |  |
Business Acquisition, Effective Date of Acquisition | Feb. 28, 2018 |
Percentage of Outstanding Common Stock Acquired | 100.00% |
Business Combination, Consideration Transferred | $ 181,043,000 |
Number of Shares Issued for Aquisition | 4,654,091 |
Cash consideration for outstanding shares | $ 0 |
Effective settlement of a pre-existing relationship | 0 |
Loans receivable | 627,767,000 |
Loans Receivable Acquired, Gross Principal and Contractual Interest Due | 632,370,000 |
Third-party Acquisition Related Costs | 1,239,000 |
Net interest income and non-interest income | 4,234,000 |
Net income | $ 998,000 |
Collegiate Peaks Bank |  |
Business Acquisition |  |
Business Acquisition, Effective Date of Acquisition | Jan. 31, 2018 |
Percentage of Outstanding Common Stock Acquired | 100.00% |
Business Combination, Consideration Transferred | $ 96,083,000 |
Number of Shares Issued for Aquisition | 1,778,777 |
Cash consideration for outstanding shares | $ 16,265,000 |
Effective settlement of a pre-existing relationship | 10,054,000 |
Loans receivable | 354,252,000 |
Loans Receivable Acquired, Gross Principal and Contractual Interest Due | 355,364,000 |
Third-party Acquisition Related Costs | 590,000 |
Net interest income and non-interest income | 3,792,000 |
Net income | $ 1,212,000 |

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- Definition Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e845-128460 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e848-128460 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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- Definition Number of shares of equity interests issued or issuable to acquire entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
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- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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- Definition Fair value of acquired receivable from business combination, excluding certain loans and debt securities acquired in transfer. + 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 (b)(1) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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- Definition For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables. + 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 (b)(2) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e1043-128460 + Details
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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 + Details
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- Definition This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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- Definition This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463 + Details
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- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585 + Details
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