Securities Held-to-Maturity - Schedule of Unrealized Gains, Losses and Fair Value of Securities Held-to-Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Held-to-maturity cost or amortized cost	$ 411	$ 451
Held-to-maturity gross unrealized gains	20	30
Held-to-maturity gross unrealized losses	(1)	(12)
Held-to-maturity fair value	$ 430	$ 469

Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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- Definition

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

+ References

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- Definition

Amount, before other-than-temporary impairment (OTTI) accretion, of investment in debt securities measured at amortized cost (held-to-maturity).

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=SL120269820-111563

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- References

No definition available.

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