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Fair Value Measurements, Measured On Recurring Basis Significant Unobservable Inputs (Details) - Fair Value, Recurring [Member] - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2020 | Mar. 31, 2019
Available-for-sale securities [Member] | Other debt securities [Member] |  |  |  |
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward] |  |  |  |
Balance, beginning of period | $ 472 |  | $ 472 |
Transfer to Level 3 from Level 2 | 0 | [1] | 0 | [2]
Purchases | 0 |  | 0 |
Proceeds from sales | 0 |  | 0 |
Redemptions and distributions | 0 |  | 0 |
Other comprehensive income (loss) | 0 |  | 0 |
Balance, end of period | 472 |  | 472 |
Available-for-sale securities [Member] | Other debt securities [Member] | Mortgage banking revenue [Member] |  |  |  |
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward] |  |  |  |
Gain (loss) recognized in earnings | 0 |  | 0 |
Residential mortgage loans held for sale [Member] |  |  |  |
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward] |  |  |  |
Balance, beginning of period | 8,313 |  | 15,207 |
Transfer to Level 3 from Level 2 | 2,264 | [1] | 982 | [2]
Purchases | 0 |  | 0 |
Proceeds from sales | (940) |  | (381) |
Redemptions and distributions | 0 |  | 0 |
Other comprehensive income (loss) | 0 |  | 0 |
Balance, end of period | 9,574 |  | 15,776 |
Residential mortgage loans held for sale [Member] | Mortgage banking revenue [Member] |  |  |  |
Fair Value Assets Measured on Recurring Basis Unobservable Reconciliation [Roll Forward] |  |  |  |
Gain (loss) recognized in earnings | $ (63) |  | $ (32) |
[1] | Recurring transfers to Level 3 from Level 2 consist of residential mortgage loans intended for sale to U.S. government agencies that fail to meet conforming standards.
[2] | Recurring transfers to Level 3 from Level 2 consist of residential mortgage loans intended for sale to U.S. government agencies that fail to meet conforming standards.

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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + 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 (c)(1) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3). + 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 (c)(1a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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