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Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands | 10 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Goodwill [Line Items] |  |  |  |
Goodwill, adjustments during measurement period |  | $ 94 | $ 0 |
Goodwill acquired |  | 0 | 115,944 |
Acquisition of core deposits | $ 4,500 |  | 4,500 |
Acquisition of wealth management relationships | 100 |  | 100 |
Acquisition of insurance contract relationships | 300 |  | 300 |
Finite-lived Intangible Assets Acquired |  | 0 | 5,713 |
Amortization expense on finite-lived intangible assets |  | 1,615 | 1,818 | $ 1,129
Integrity Bancshares, Inc. |  |  |  |
Goodwill [Line Items] |  |  |  |
Goodwill, adjustments during measurement period | $ (1,100) | $ 100 |  |
Goodwill acquired |  |  | 115,900 |
Finite-lived Intangible Assets Acquired |  |  | $ 5,700 |

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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 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=66902209&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=66006027&loc=d3e16323-109275 + Details
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- Definition Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition. + 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 (b) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + 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 Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e961-128460 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -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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