CREDIT QUALITY ASSESSMENT (Impaired Loans by Portfolio) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	$ 20,211	$ 23,179	$ 26,382
Contractual interest income due on impaired loans during the period	2,513	2,314	2,082
Interest income on impaired loans recognized on a cash basis	506	754	511
Interest income on impaired loans recognized on an accrual basis	138	169	$ 186
Commercial
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	7,685	7,903
Contractual interest income due on impaired loans during the period	858	828
Interest income on impaired loans recognized on a cash basis	215	204
Interest income on impaired loans recognized on an accrual basis	63	111
All Other
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	2,237	2,968
Contractual interest income due on impaired loans during the period	143	84
Interest income on impaired loans recognized on a cash basis	96	132
Interest income on impaired loans recognized on an accrual basis	75	32
Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	770	137
Contractual interest income due on impaired loans during the period	495	333
Interest income on impaired loans recognized on a cash basis	0	0
Interest income on impaired loans recognized on an accrual basis	0	0
Commercial Real Estate Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	5,696	6,835
Contractual interest income due on impaired loans during the period	610	669
Interest income on impaired loans recognized on a cash basis	20	24
Interest income on impaired loans recognized on an accrual basis	0	0
Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	3,823	5,336
Contractual interest income due on impaired loans during the period	407	400
Interest income on impaired loans recognized on a cash basis	175	394
Interest income on impaired loans recognized on an accrual basis	$ 0	$ 26

Loans and Leases Receivable, Impaired, Contractual Interest Income

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- Definition

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+ References

No definition available.

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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+ References

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