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Fair Value Accounting and Measurement (IRL rollforward) (Details) - Interest Rate Lock Commitments Contracts - Fair Value, Inputs, Level 3 [Member] - Fair Value, Recurring [Member] - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |  |
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Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Jun. 30, 2021 | Dec. 31, 2020 | Jun. 30, 2020 | Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |  |  |  |  |
Balance - Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value | $ 482 | $ 169 | $ 482 | $ 169 | $ 585 | $ 1,096 | $ 0 | $ 0
Change included in Earnings - Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings | 1,864 | 169 | 5,708 | 169 |  |  |  |
Settlements - Fair Value Net Derivative Asset (Liability) Measured on Recurring Basis with Unobserved Inputs reconciliation, Sales and Settlements | $ (1,967) | $ 0 | $ (6,322) | $ 0 |  |  |  |

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- Definition Fair Value Net Derivative Asset (Liability) Measured on Recurring Basis with Unobserved Inputs reconciliation, Sales and Settlements + References No definition available. + Details
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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. + Details
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- Definition Fair value 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) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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- Definition Amount of gain (loss) recognized in income from derivative asset (liability) after deduction of derivative liability (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=123874694&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19279-110258 + Details
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