Amount of realized gain on 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 320
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-Section 50
-Paragraph 9
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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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

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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)
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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).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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No definition available.

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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.

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

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Securities - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
Securities - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2007
Debt Securities, Available-for-sale [Line Items]
Gross gains			$ 0		$ 0	$ 3,600
Debt Securities, Available-for-sale, Realized Loss	$ 0			$ 0
Gain (loss) on sale of equity securities	0		$ 0	295	$ (14)
Collateral Pledged [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Restricted	$ 2,200	$ 2,700		$ 2,200		2,700
Other Investments [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Debt Securities, Available-for-sale [Line Items]
Investments, Fair Value Disclosure		3,427				3,427
Fair Value, Inputs, Level 3 [Member] \| Other Investments [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Debt Securities, Available-for-sale [Line Items]
Investments, Fair Value Disclosure		$ 3,427				$ 3,427
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)				(25,702)