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Securities - Unrealized Gains (Losses) of Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Total unrealized gains/(losses) on debt securities available-for-sale, Gross Unrealized Gains	$ 35,448	$ 11,659
Total unrealized gains/(losses) on debt securities available-for-sale, Gross Unrealized Losses	(1)	(953)
Total unrealized gains/(losses) on debt securities available-for-sale, Net Unrealized Gains/(Losses)	35,447	10,706
Income tax (expense) benefit, Gross Unrealized Gains	(7,548)	(2,486)
Income tax (expense) benefit, Gross Unrealized Losses	0	203
Income tax (expense) benefit, Net Unrealized Gains/(Losses)	(7,548)	(2,283)
Net Unrealized Gains/(Losses), Net of Tax Included in Accumulated Other Comprehensive Loss, Gross Unrealized Gains	27,900	9,173
Net Unrealized Gains/(Losses), Net of Tax Included in Accumulated Other Comprehensive Loss, Gross Unrealized Losses	(1)	(750)
Net Unrealized Gains/(Losses), Net of Tax Included in Accumulated Other Comprehensive Loss, Net Unrealized Gains/(Losses)	$ 27,899	$ 8,423

X

- Definition

Accumulated Other Comprehensive Income (Loss), Debt Securities Available For Sale Gross Unrealized Gain Adjustment Net Of Tax

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Amount, after tax, of accumulated unrealized gain (loss) 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/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e681-108580

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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-Topic 320
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