Investment and Equity Securities - Investment Securities - Gross Unrealized Losses and Fair Value of Investments (Detail) $ in Thousands	Jun. 30, 2021 USD ($)
Schedule Of Held To Maturity Securities [Line Items]
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Fair Value	$ 1,244
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Unrealized Losses	6
Securities held to maturity, Gross unrealized losses, Fair Value	1,244
Securities held to maturity, Gross unrealized losses, Unrealized Losses	6
Corporate Bonds [Member]
Schedule Of Held To Maturity Securities [Line Items]
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Fair Value	1,244
Securities held to maturity, Gross unrealized losses, Less than Twelve Months, Unrealized Losses	6
Securities held to maturity, Gross unrealized losses, Fair Value	1,244
Securities held to maturity, Gross unrealized losses, Unrealized Losses	$ 6

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

+ Details

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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

Reference 2: 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

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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