CREDIT QUALITY ASSESSMENT (Troubled Debt Restructured Loans for Specific Segments of the Loan Portfolio) (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Financing Receivable Modifications [Line Items]
Restructured accruing	$ 0	$ 492
Restructured non-accruing	1,622	1,559
Balance	1,622	2,051
Specific allowance	563	247
Restructured and subsequently defaulted	0	0
Commercial
Financing Receivable Modifications [Line Items]
Restructured accruing	0	492
Restructured non-accruing	1,464	1,019
Balance	1,464	1,511
Specific allowance	563	247
Restructured and subsequently defaulted	0	0
All Other
Financing Receivable Modifications [Line Items]
Restructured accruing	0	0
Restructured non-accruing	0	0
Balance	0	0
Specific allowance	0	0
Restructured and subsequently defaulted	0	0
Commercial Portfolio Segment \| Commercial Acquisition, Development and Construction
Financing Receivable Modifications [Line Items]
Restructured accruing	0	0
Restructured non-accruing	0	0
Balance	0	0
Specific allowance	0	0
Restructured and subsequently defaulted	0	0
Commercial Portfolio Segment \| Commercial Investor Real Estate
Financing Receivable Modifications [Line Items]
Restructured accruing	0	0
Restructured non-accruing	0	0
Balance	0	0
Specific allowance	0	0
Restructured and subsequently defaulted	0	0
Commercial Portfolio Segment \| Commercial Owner Occupied Real Estate
Financing Receivable Modifications [Line Items]
Restructured accruing	0	0
Restructured non-accruing	158	540
Balance	158	540
Specific allowance	0	0
Restructured and subsequently defaulted	$ 0	$ 0

- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

No definition available.

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months.

+ References

No definition available.

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which restructured accruing.

+ References

No definition available.

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which restructured non accruing.

+ References

No definition available.

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings previous 12 months, for specific allowance.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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