Combined percentage of commercial real estate and commercial construction in commercial loans.

No definition available.

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- Definition

Combined percentage of commercial real estate and commercial construction in portfolio loans.

+ References

No definition available.

+ Details

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- Definition

Commitment to lend additional funds.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Financial receivable trouble debt restructuring reclassified to accruing trouble debt restructuring status.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Loans modified not considered to be troubled debt restructuring.

+ References

No definition available.

+ Details

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- Definition

Maximum concentration of commercial real estate and commercial construction portfolio in loans.

+ References

No definition available.

+ Details

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- Definition

Net Loans Out Of State, Percentage

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Number Of Loans Modified Not Considered To Be Troubled Debt Restructuring

+ References

No definition available.

+ Details

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- Definition

Number of troubled debt restructuring loans returned back to accruing status.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Out of state exposure of combined portfolio.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Percentage of commercial loans in portfolio loans.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Period of loans in default treated as troubled debt restructuring.

+ 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.

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Period Type:	duration

- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of the receivables acquired, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

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-Publisher FASB
-Name Accounting Standards Codification
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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

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-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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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
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-Section 45
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-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

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

Reference 1: 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

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Balance Type:	debit
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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes 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 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. 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 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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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