Off-Balance Sheet Activities - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Small Business Investment Corporations
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Capital contributions	$ 5,831	$ 3,905
Low Income Housing Partnerships
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Capital contributions	4,190	1,434
Capital Contributions, Small Business Investment Corporation
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Capital contributions	9,669	6,595
Capital Contributions, Low Income Housing Partnerships
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Capital contributions	$ 4,810	$ 4,566
Minimum
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fixed Interest rate loan	2.53%	2.45%
Fixed rate loan maturities range	1 year	1 year
Maximum
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fixed Interest rate loan	18.00%	18.00%
Fixed rate loan maturities range	30 years	35 years

Fixed rate loan maturities range.

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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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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Total contributions made by each class of partners (i.e., general, limited and preferred partners).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 4.F)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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