Basis of presentation and summary of significant accounting policies.

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- Definition

Delinquency period placed on nonaccrual status loan.

+ References

No definition available.

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- Definition

Percentage of available for sale securities held.

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No definition available.

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- Definition

Amount of allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
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-Name Accounting Standards Codification
-Topic 326
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
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- Definition

Amount of the cumulative effect on retained earnings net of related income tax effect.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794

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- Definition

Amount of the related income tax effect of a cumulative effect on retained earnings.

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- Definition

Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

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- Definition

Threshold period for when financing receivable is considered past due, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes threshold period past due to write off as uncollectible.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)		3 Months Ended	12 Months Ended
	Jan. 01, 2020	Mar. 31, 2020	Dec. 31, 2019
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Increase to retained earnings for cumulative effect of adopting ASU tax		$ 925,000
Addition of allowance for credit losses for financial assets purchased with credit deterioration		502,000
Accrued interest receivable		27,400,000	$ 27,400,000
ASU No. 2016-13 [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Increase to retained earnings for cumulative effect of adopting ASU	$ 2,300,000
Increase to retained earnings for cumulative effect of adopting ASU tax	925,000
Addition of allowance for credit losses for financial assets purchased with credit deterioration	$ 1,200,000
Accrued interest receivable		$ 27,400,000
Delinquency period placed on nonaccrual status loan		90 days
Commercial loans are charged off deemed uncollectible period		180 days
ASU No. 2016-13 [Member] \| U.S. Treasury [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of available for sale securities held		95.00%	95.00%
ASU No. 2016-13 [Member] \| U.S. Government-sponsored Entities and Agencies [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Percentage of available for sale securities held		95.00%	95.00%