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Goodwill and Other Intangible Assets - Additional Information (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2015 USD ($) event | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract] |  |  |
Goodwill acquired | $ 115,944 | $ 0 |
Acquisition of core deposits | 6,100 |  |
Acquisition of wealth management relationships | 100 |  |
Acquisition of insurance contract relationships | 400 |  |
Finite-lived Intangible Assets Acquired | $ 5,713 | 0 |
Number of triggering events | event | 0 |  |
Amortization expense on finite-lived intangible assets | $ 1,818 | $ 1,129 | $ 1,591

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- Definition Intangible assets arising from core deposits acquired in business combination. + References No definition available. + Details
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- Definition Intangible assets arising from wealth management acquired in business combination. + References No definition available. + Details
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- Definition Number of triggering events for impairment analysis. + References No definition available. + Details
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 Reference 2: 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=56944662&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275 + Details
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- Definition Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, resulting from a business combination. + References No definition available. + Details
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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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- Definition Carrying amount as of the balance sheet date of the intangible assets from insurance contracts acquired in a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section S99 -Paragraph 2 -Subparagraph (2) -URI http://asc.fasb.org/extlink&oid=27015749&loc=d3e569990-122904 + Details
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