Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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Period Type:	instant

- Definition

Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714

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Balance Type:	credit
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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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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.

+ Details

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- Definition

Number of shares issued which are neither cancelled nor held in the treasury.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	instant

- Details

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- Details

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Securities - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Securities - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2007	Mar. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Gain on sale of equity securities	$ 295
Collateral Pledged [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Restricted			$ 1,500	$ 2,000
Common Class B [Member]
Debt Securities, Available-for-sale [Line Items]
Sale of Stock, Number of Shares Issued in Transaction	(25,702)
Visa Inc's Initial Public Offering [Member] \| Common Class B [Member]
Debt Securities, Available-for-sale [Line Items]
Sale of Stock, Number of Shares Issued in Transaction		(51,404)
Shares, Outstanding				(25,702)