CREDIT QUALITY ASSESSMENT (Credit Quality of Loan Portfolio) (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	$ 19,961	$ 13,417
Non-accrual loans	26,588	26,336
Loans aquired with deteriorated credit quality	23,573
Current loans	5,991,429	4,274,495
Total loans	6,061,551	4,314,248
Commercial
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	4,371	587
Non-accrual loans	6,634	6,703
Loans aquired with deteriorated credit quality	2,268
Current loans	639,524	490,658
Total loans	652,797	497,948
Consumer
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	3,152	2,213
Non-accrual loans	3,244	2,967
Loans aquired with deteriorated credit quality	1,383
Current loans	525,194	450,649
Total loans	532,973	455,829
Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
Non-accrual loans	136	136
Loans aquired with deteriorated credit quality	0
Current loans	564,735	292,307
Total loans	564,871	292,443
Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	976	775
Non-accrual loans	5,813	5,575
Loans aquired with deteriorated credit quality	17,573
Current loans	1,904,077	1,106,360
Total loans	1,928,439	1,112,710
Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	1,378	414
Non-accrual loans	3,524	3,582
Loans aquired with deteriorated credit quality	2,337
Current loans	1,167,500	853,200
Total loans	1,174,739	857,196
Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	9,497	9,428
Non-accrual loans	7,063	7,196
Loans aquired with deteriorated credit quality	12
Current loans	975,715	904,811
Total loans	992,287	921,435
Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	587	0
Non-accrual loans	174	177
Loans aquired with deteriorated credit quality	0
Current loans	214,684	176,510
Total loans	215,445	176,687
31-60 days
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	13,462	9,983
31-60 days \| Commercial
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	3,834	587
31-60 days \| Consumer
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	2,061	2,107
31-60 days \| Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
31-60 days \| Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	727	775
31-60 days \| Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	605	414
31-60 days \| Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	5,648	6,100
31-60 days \| Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	587	0
61-90 days
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	6,373	3,209
61-90 days \| Commercial
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	537	0
61-90 days \| Consumer
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	965	106
61-90 days \| Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
61-90 days \| Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	249	0
61-90 days \| Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	773	0
61-90 days \| Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	3,849	3,103
61-90 days \| Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
> 90 days
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	126	225
> 90 days \| Commercial
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
> 90 days \| Consumer
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	126	0
> 90 days \| Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
> 90 days \| Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
> 90 days \| Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	0
> 90 days \| Residential Real Estate Portfolio Segment \| Residential Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	0	225
> 90 days \| Residential Real Estate Portfolio Segment \| Residential Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Total past due	$ 0	$ 0

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
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Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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Amount before allowance and after 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. 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 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
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