CREDIT QUALITY ASSESSMENT (Troubled Debt Restructured Loans for Specific Segments of the Loan Portfolio) (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Financing Receivable Modifications [Line Items]
Restructured accruing	$ 0	$ 492
Restructured non-accruing	14	1,559
Balance	14	2,051
Specific allowance	14	247
Restructured and subsequently defaulted	0	0
Commercial
Financing Receivable Modifications [Line Items]
Restructured accruing	0	492
Restructured non-accruing	14	1,019
Balance	14	1,511
Specific allowance	14	247
Restructured and subsequently defaulted	0	0
All Other
Financing Receivable Modifications [Line Items]
Restructured accruing	0	0
Restructured non-accruing	14	0
Balance	14	0
Specific allowance	0	0
Restructured and subsequently defaulted	0	0
Troubled Debt Restructuring \| Commercial
Financing Receivable Modifications [Line Items]
Specific allowance		247
Restructured and subsequently defaulted		0
Troubled Debt Restructuring \| All Other
Financing Receivable Modifications [Line Items]
Specific allowance		0
Restructured and subsequently defaulted		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	0	540
Balance	0	540
Specific allowance	0	0
Restructured and subsequently defaulted	$ 0	0
Commercial Portfolio Segment \| Troubled Debt Restructuring \| Commercial Acquisition, Development and Construction
Financing Receivable Modifications [Line Items]
Specific allowance		0
Restructured and subsequently defaulted		0
Commercial Portfolio Segment \| Troubled Debt Restructuring \| Commercial Investor Real Estate
Financing Receivable Modifications [Line Items]
Specific allowance		0
Restructured and subsequently defaulted		0
Commercial Portfolio Segment \| Troubled Debt Restructuring \| Commercial Owner Occupied Real Estate
Financing Receivable Modifications [Line Items]
Specific allowance		0
Restructured and subsequently defaulted		$ 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.

+ Details

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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.

+ Details

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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.

+ References

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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

No definition available.

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