CREDIT QUALITY ASSESSMENT (Impaired Loans by Portfolio) (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	$ 19,712	$ 19,712	$ 23,179
Contractual interest income due on impaired loans during the period		1,888	2,314
Interest income on impaired loans recognized on a cash basis		473	754
Interest income on impaired loans recognized on an accrual basis		109	169
Commercial
Financing Receivable Impaired [Line Items]
Average impaired loans for the period		7,710	7,903
Contractual interest income due on impaired loans during the period		736	828
Interest income on impaired loans recognized on a cash basis		227	204
Interest income on impaired loans recognized on an accrual basis		53	111
All Other
Financing Receivable Impaired [Line Items]
Average impaired loans for the period		2,364	2,968
Contractual interest income due on impaired loans during the period		108	84
Interest income on impaired loans recognized on a cash basis		96	132
Interest income on impaired loans recognized on an accrual basis		56	32
Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Impaired [Line Items]
Average impaired loans for the period		136	137
Contractual interest income due on impaired loans during the period		283	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		5,782	6,835
Contractual interest income due on impaired loans during the period		478	669
Interest income on impaired loans recognized on a cash basis		21	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		3,720	5,336
Contractual interest income due on impaired loans during the period		283	400
Interest income on impaired loans recognized on a cash basis		129	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://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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- 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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