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Loans and Loans Held for Sale - Additional Information (Detail) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2015 USD ($) tdr loan | Dec. 31, 2014 USD ($) loan | Mar. 04, 2015 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans and Leases Receivable, Deferred Income | $ 3,200,000 | $ 2,100,000 |
Unamortized discount related to purchase accounting fair value adjustments | 10,900,000 | 2,000,000 |
Loans | 5,062,933,000 | 3,871,716,000 |
Loans held for sale | $ 35,321,000 | $ 2,970,000 |
Percentage of commercial loans in total portfolio loans | 76.00% | 75.00% |
Portfolio loans, net of unearned income | $ 3,836,877,000 | $ 2,892,522,000 |
Maximum concentration of commercial real estate and commercial construction portfolio in loans | 7.00% | 9.00% |
Number of loan modified | loan | 39 |  |
Commitment to lend additional funds on TDRs | $ 0 |  |
Number of TDRs returned back to accruing status | 8 | 9 |
Financial receivable trouble debt restructuring reclassified to accruing trouble debt restructuring status | $ 400,000 | $ 1,900,000 |
Minimum period of loan payment defaults following restructure for TDRs to be in default | 90 days |  |
Commercial Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | $ 2,166,603,000 | 1,682,236,000 |
Portfolio loans, net of unearned income | $ 2,166,603,000 | 1,682,236,000 |
Number of loan modified | loan | 8 |  |
Loans modified not considered to be troubled debt restructuring | $ 6,100,000 |  |
Commercial Construction |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 413,444,000 | 216,148,000 |
Portfolio loans, net of unearned income | $ 413,444,000 | 216,148,000 |
Number of loan modified | loan | 14 |  |
Loans modified not considered to be troubled debt restructuring | $ 8,500,000 |  |
Residential Mortgage |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | $ 639,372,000 | 489,586,000 |
Number of loan modified | loan | 2 |  |
Loans modified not considered to be troubled debt restructuring | $ 100,000 |  |
Installment and Other Consumer |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 73,939,000 | $ 65,567,000 |
Loans held for sale | 23,300,000 |  |
CRE and Commercial Construction |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Portfolio loans, net of unearned income | $ 2,600,000,000 |  |
Combined percentage of commercial real estate and commercial construction in total commercial loans | 67.00% | 66.00% |
Combined percentage of commercial real estate and commercial construction in total portfolio loans | 51.00% | 49.00% |
Out-of-state exposure of combined portfolio | 5.80% | 8.00% |
Percentage of total loans out-of-state | 3.00% | 3.90% |
Commercial and Industrial |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | $ 1,256,830,000 | $ 994,138,000 |
Portfolio loans, net of unearned income | $ 1,256,830,000 | 994,138,000 |
Number of loan modified | loan | 11 |  |
Loans modified not considered to be troubled debt restructuring | $ 7,800,000 |  |
Home Equity |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | $ 470,845,000 | 418,563,000 |
Number of loan modified | loan | 4 |  |
Loans modified not considered to be troubled debt restructuring | $ 400,000 |  |
Consumer Construction |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 6,579,000 | $ 2,508,000 |
Integrity Bancshares, Inc. |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 673,300,000 |  |
Loans | 788,687,000 |  | $ 788,700,000
Integrity Bancshares, Inc. | Commercial Real Estate |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 293,200,000 |  |
Loans |  |  | 331,600,000
Integrity Bancshares, Inc. | Commercial Construction |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 69,200,000 |  |
Loans |  |  | 92,400,000
Integrity Bancshares, Inc. | Residential Mortgage |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 115,600,000 |  |
Loans |  |  | 116,900,000
Integrity Bancshares, Inc. | Home Equity, Installment and Other Consumer Construction |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  |  | 27,500,000
Integrity Bancshares, Inc. | CRE and Commercial Construction |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | 424,000,000 |  |
Integrity Bancshares, Inc. | Home Equity |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  |  | 25,600,000
Integrity Bancshares, Inc. | Consumer Construction |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  |  | 1,900,000
Integrity Bancshares, Inc. | Consumer Borrower |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans |  |  | 36,100,000
Commercial and Industrial | Integrity Bancshares, Inc. |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans | $ 167,700,000 |  |
Loans |  |  | $ 184,200,000

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- Definition Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6378556&loc=d3e10152-111534 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738 + Details
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- Definition Reflects the aggregate gross carrying amount of all commercial loans and leases held in portfolio, prior to deducting deferred income and the allowance for losses on commercial loans and leases. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5066-111524 + Details
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