CREDIT QUALITY ASSESSMENT - Restructured Loans at the date of Restructuring For Specific Segments of the Loan Portfolio (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	$ 512	$ 4,533
Individual allowance	332	1,020
Restructured and subsequently defaulted	0	0
All Other Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	0	549
Individual allowance	0	0
Restructured and subsequently defaulted	0	0
Troubled debt restructurings:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	929
Restructured non-accruing	512	3,604
Troubled debt restructurings: \| All Other Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	549
Restructured non-accruing	0	0
Commercial real estate: \| Commercial investor real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	0	723
Individual allowance	0	65
Restructured and subsequently defaulted	0	0
Commercial real estate: \| Commercial owner-occupied real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	0	930
Individual allowance	0	0
Restructured and subsequently defaulted	0	0
Commercial real estate: \| Commercial AD&C
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	0	0
Individual allowance	0	0
Restructured and subsequently defaulted	0	0
Commercial real estate: \| Troubled debt restructurings: \| Commercial investor real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	0
Restructured non-accruing	0	723
Commercial real estate: \| Troubled debt restructurings: \| Commercial owner-occupied real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	0
Restructured non-accruing	0	930
Commercial real estate: \| Troubled debt restructurings: \| Commercial AD&C
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	0
Restructured non-accruing	0	0
Commercial Business
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	512	2,331
Individual allowance	332	955
Restructured and subsequently defaulted	0	0
Commercial Business \| Troubled debt restructurings:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Restructured accruing	0	380
Restructured non-accruing	$ 512	$ 1,951

- 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.

+ 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 non accruing.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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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