Investment Securities - Summary of Available-For-Sale Securities and Held to Maturity Securities, Continuous Unrealized Loss Position, Fair Value (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value	$ 16,425	$ 14,723
Less than 12 months unrealized losses	(369)	(193)
Fair value	16,425	14,723
Unrealized losses	(369)	(193)
Mortgage backed securities [Member]
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value	9,947	4,481
Less than 12 months unrealized losses	(97)	(17)
Fair value	9,947	4,481
Unrealized losses	(97)	(17)
Government agencies [Member]
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value		2,412
Less than 12 months unrealized losses		(6)
Fair value		2,412
Unrealized losses		(6)
Corporate bonds [Member]
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value	6,478	7,830
Less than 12 months unrealized losses	(272)	(170)
Fair value	6,478	7,830
Unrealized losses	$ (272)	$ (170)

Investments debt and equity securities.

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- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

+ 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

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

+ Details

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- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months.

+ References

No definition available.

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- Definition

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

No definition available.

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