CREDIT QUALITY ASSESSMENT (Impaired Loans by Portfolio) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	$ 23,179	$ 26,382	$ 29,828
Contractual interest income due on impaired loans during the period	2,314	2,082	2,527
Interest income on impaired loans recognized on a cash basis	754	511	961
Interest income on impaired loans recognized on an accrual basis	169	186	$ 274
Commercial
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	7,903	5,646
Contractual interest income due on impaired loans during the period	828	570
Interest income on impaired loans recognized on a cash basis	204	153
Interest income on impaired loans recognized on an accrual basis	111	107
All Other
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	2,968	4,545
Contractual interest income due on impaired loans during the period	84	190
Interest income on impaired loans recognized on a cash basis	132	49
Interest income on impaired loans recognized on an accrual basis	32	42
Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	137	150
Contractual interest income due on impaired loans during the period	333	294
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	6,835	9,480
Contractual interest income due on impaired loans during the period	669	718
Interest income on impaired loans recognized on a cash basis	24	43
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	5,336	6,561
Contractual interest income due on impaired loans during the period	400	310
Interest income on impaired loans recognized on a cash basis	394	266
Interest income on impaired loans recognized on an accrual basis	$ 26	$ 37

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://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-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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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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