CREDIT QUALITY ASSESSMENT (Impaired Loans by Portfolio) (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	$ 24,175	$ 20,211
Contractual interest income due on impaired loans during the period	646	2,513
Interest income on impaired loans recognized on a cash basis	110	506
Interest income on impaired loans recognized on an accrual basis	42	138
Commercial
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	7,936	7,685
Contractual interest income due on impaired loans during the period	127	858
Interest income on impaired loans recognized on a cash basis	49	215
Interest income on impaired loans recognized on an accrual basis	13	63
All Other
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	1,720	2,237
Contractual interest income due on impaired loans during the period	34	143
Interest income on impaired loans recognized on a cash basis	5	96
Interest income on impaired loans recognized on an accrual basis	19	75
Commercial Real Estate Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	3,306	770
Contractual interest income due on impaired loans during the period	184	495
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	6,100	5,696
Contractual interest income due on impaired loans during the period	179	610
Interest income on impaired loans recognized on a cash basis	4	20
Interest income on impaired loans recognized on an accrual basis	10	0
Commercial Real Estate Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Impaired [Line Items]
Average impaired loans for the period	5,113	3,823
Contractual interest income due on impaired loans during the period	122	407
Interest income on impaired loans recognized on a cash basis	52	175
Interest income on impaired loans recognized on an accrual basis	$ 0	$ 0

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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- Definition

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+ References

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