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Mortgage Servicing Rights - Narrative (Details) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2022 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2022 USD ($) | Jun. 30, 2021 USD ($) | Dec. 31, 2021 USD ($)
Transfers and Servicing [Abstract] |  |  |  |  |
Other real estate owned | $ 3,800 |  | $ 3,800 |  | $ 3,800
Contractually specified servicing fee, late fee, and ancillary fee earned in exchange for servicing financial asset | $ 3 | $ 2 | $ 5 | $ 4 |
Fixed Rate Conventional Loans |  |  |  |  |
Servicing Asset Key Economic Assumptions [Line Items] |  |  |  |  |
Risk premium on 10-year U.S. Treasury | 0.0700 |  | 0.0700 |  |
Loans Excluding Fixed Rate Conventional Loans |  |  |  |  |
Servicing Asset Key Economic Assumptions [Line Items] |  |  |  |  |
Risk premium on 10-year U.S. Treasury | 0.0800 |  | 0.0800 |  |

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- Definition [Line Items] for The key economic assumptions used to value servicing assets. + References No definition available. + Details
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- Definition Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Risk Premium On Ten Year U.S. Treasury Rate + References No definition available. + Details
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- Definition Amount of contractually specified servicing fee, late fee, and ancillary fee recognized as income for servicing asset and servicing liability. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 2 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=128311188&loc=d3e122596-111746 + Details
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