Investment Securities Gain/Loss Sale of Securities (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Gross gains on available for sale securities	$ 3,106	$ 654	$ 9,304	$ 2,334
Gross gains on held to maturity securities	0	0	0	0
Total gains	3,106	654	9,304	2,334
Gross (losses) on available for sale securities	(11)	(13,636)	(90)	(13,636)
Gross (losses) on held to maturity securities	0	0	0	0
Total (losses)	(11)	(13,636)	(90)	(13,636)
Write-up of equity securities without readily determinable fair values	0	13,444	0	13,444
Investment securities gains (losses), net	3,096	463	9,214	2,143
Proceeds from sales of investment securities	$ 261,037	$ 803,105	$ 626,276	$ 934,228

Debt Securities, Held-to-maturity, Sold, Realized Gain

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Debt Securities, Held-to-maturity, Sold, Realized Loss

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563

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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 realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563

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Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

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The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

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