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v3.8.0.1

Premises and Equipment - Additional Information (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 USD ($) contract director | Dec. 31, 2016 USD ($) director | Dec. 31, 2015 USD ($) director
Property, Plant and Equipment [Line Items] |  |  |
Depreciation expense | $ 5.1 | $ 5.0 | $ 4.7
Lease expiration year | Jan. 01, 2054 |  |
Capital Lease Obligations, Number of Contracts | contract | 1 |  |
Rental expense | $ 4.0 | $ 4.1 | $ 3.9
Number of Directors | director | 2 | 2 | 2
Directors |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Rental expense for premises leases with two directors | $ 0.2 | $ 0.3 | $ 0.3

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- Definition Capital Lease Obligations, Number of Contracts + References No definition available. + Details
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- Definition Related Party Transaction, Number of Related Parties + References No definition available. + Details
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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
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- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References No definition available. + Details
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- Definition Date which lease or group of leases is set to expire, in CCYY-MM-DD format. + References No definition available. + Details
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- Definition This element represents the payments that the lessee is obligated to make or can be required to make in connection with a property under the terms of an agreement classified as an operating lease, excluding contingent rentals and a guarantee by the lessee of the lessor's debt and the lessee's obligation to pay (apart from the rental payments) executory costs such as insurance, maintenance, and taxes. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 25 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77910348&loc=d3e34039-112682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697 + Details
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- Definition 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. + References No definition available. + Details
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- Details
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