Comprehensive Income - Accumulated Other Comprehensive Income (loss) (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income Loss [Line Items]
Tax effect on amount reclassified from accumulated other comprehensive income	$ 11	$ 0
Unrealized Holding Gains on Available-for-Sale Securities (Net) [Member]
Accumulated Other Comprehensive Income Loss [Line Items]
Tax effect on Other Comprehensive income (loss) before reclassifications	(490)	(219)
Tax effect on amount reclassified from accumulated other comprehensive income	$ 11	$ 0

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.

No definition available.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 20
-Section 45
-Paragraph 11
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109238882&loc=d3e39076-109324

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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-Topic 320
-SubTopic 10
-Section 50
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