Fair Value Measurements - Debt Securities (Details) - Mortgage banking derivatives - Pricing Model - Fair Value, Inputs, Level 3 - Measurement Input, Pull Through Rate $ in Thousands	Sep. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value	$ 6,015	$ 280
Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.7844	0.7625
Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.699
Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.814

Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in net income (trading).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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.

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- Definition

Amount of 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 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

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