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Securities - Unrealized Gains (Losses) of Debt Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Total unrealized gains/(losses) on debt securities available-for-sale, Gross Unrealized Gains	$ 11,816	$ 3,514
Total unrealized gains/(losses) on debt securities available-for-sale, Gross Unrealized Losses	(564)	(8,628)
Total unrealized gains/(losses) on debt securities available-for-sale, Net Unrealized (Losses)/Gains	11,252	(5,114)
Income tax (expense) benefit, Gross Unrealized Gains	(2,520)	(746)
Income tax (expense) benefit, Gross Unrealized Losses	120	1,832
Income tax (expense) benefit, Net Unrealized (Losses)/Gains	(2,400)	1,086
Net Unrealized (Losses)/Gains, Net of Tax Included in Accumulated Other Comprehensive Loss, Gross Unrealized Gains	9,296	2,768
Net Unrealized (Losses)/Gains, Net of Tax Included in Accumulated Other Comprehensive Loss, Gross Unrealized Losses	(444)	(6,796)
Net Unrealized (Losses)/Gains, Net of Tax Included in Accumulated Other Comprehensive Loss, Net Unrealized (Losses)/Gains	$ 8,852	$ (4,028)

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- Definition

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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=118930883&loc=d3e681-108580

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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-Topic 320
-SubTopic 10
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