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Disclosures about Fair Value of Assets and Liabilities - Quantitative Information about Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements (Detail) $ in Thousands	3 Months Ended
	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Discount Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights	$ 853	$ 888
Marketability Discount [Member] | Market Comparable Properties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Impaired loans (collateral-dependent)	$ 33
Impaired loans (collateral-dependent)	0.111
Comparability Adjustments [Member] | Market Comparable Properties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Foreclosed assets	$ 512
Minimum [Member] | Discount Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.095	0.095
Minimum [Member] | Constant Prepayment Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.083	0.088
Minimum [Member] | Probability of Default [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.0005	0.0005
Maximum [Member] | Discount Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.115	0.115
Maximum [Member] | Constant Prepayment Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.110	0.111
Maximum [Member] | Probability of Default [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.0012	0.0012
Maximum [Member] | Comparability Adjustments [Member] | Market Comparable Properties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Foreclosed assets	0.078
Weighted Average [Member] | Discount Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.095	0.095
Weighted Average [Member] | Constant Prepayment Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.090	0.097
Weighted Average [Member] | Probability of Default [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.0011	0.0011
Weighted Average [Member] | Marketability Discount [Member] | Market Comparable Properties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Impaired loans (collateral-dependent)	0.111
Weighted Average [Member] | Comparability Adjustments [Member] | Market Comparable Properties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Foreclosed assets	0.078

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- Definition

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+ References

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X

- Definition

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+ References

No definition available.

+ Details

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- Definition

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+ References

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+ Details

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- Definition

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+ References

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- Definition

Mortgage servicing rights fair value disclosure.

+ References

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+ Details

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- Definition

Mortgage servicing rights measurement input.

+ References

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+ 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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