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Premises and Equipment - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Property, Plant and Equipment [Line Items] |  |  |
Sale Leaseback Transaction, Annual Rental Payments | $ 141 |  |
Gain on sale of branch | $ 297 |  |
Sale-leaseback transaction | 15 year |  |
Total lease expense | $ 2,700 | $ 3,700 | $ 2,900
Premises and Equipment [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Depreciation included in noninterest expense | $ 9,000 | $ 7,500 | $ 7,200

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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 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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- Definition The yearly payments due under the lease entered into in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84164451&loc=d3e36991-112694 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77913982&loc=d3e50796-112755 + Details
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- Definition The portion of the deferred gain that was recognized in the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 40 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77907795&loc=d3e50609-112754 + Details
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- Definition A description of the terms of the lease(s) related to the assets being leased-back in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=77913982&loc=d3e50796-112755 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84164451&loc=d3e36991-112694 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 40 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888430&loc=SL77919786-209982 + Details
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- Details
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