Investment and Equity Securities - Investment Securities - Gross Unrealized Losses and Fair Value of Investments (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Schedule Of Held To Maturity Securities [Line Items]
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Fair Value	$ 23,902	$ 5,201
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Unrealized Losses	857	49
Securities held to maturity, Gross unrealized losses, Fair Value	23,902	5,201
Securities held to maturity, Gross unrealized losses, Unrealized Losses	857	49
U.S. Government Agencies [Member]
Schedule Of Held To Maturity Securities [Line Items]
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Fair Value	152
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Unrealized Losses	3
Securities held to maturity, Gross unrealized losses, Fair Value	152
Securities held to maturity, Gross unrealized losses, Unrealized Losses	3
State and Political Subdivisions [Member]
Schedule Of Held To Maturity Securities [Line Items]
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Fair Value	11,750
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Unrealized Losses	363
Securities held to maturity, Gross unrealized losses, Fair Value	11,750
Securities held to maturity, Gross unrealized losses, Unrealized Losses	363
Corporate Bonds [Member]
Schedule Of Held To Maturity Securities [Line Items]
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Fair Value	12,000	5,201
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Unrealized Losses	491	49
Securities held to maturity, Gross unrealized losses, Fair Value	12,000	5,201
Securities held to maturity, Gross unrealized losses, Unrealized Losses	$ 491	$ 49

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

+ References

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- Definition

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for less than 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27290-111563

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27337-111563

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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for less than 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27337-111563

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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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