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Mortgage Banking Activity - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2022 | Jun. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021
Mortgage Banking [Line Items] |  |  |  |  |  |
Net loans and leases | $ 56,690 |  |  | $ 56,690 |  | $ 54,189
Mortgage banking and title income | 9 |  | $ 34 | 65 | $ 126 |
Gain on sale of mortgage servicing rights |  |  |  | 12 | 0 |
Mortgage banking and title income |  |  |  |  |  |
Mortgage Banking [Line Items] |  |  |  |  |  |
Mortgage banking and title income | 1 |  | $ 1 | 4 | $ 2 |
Sale of mortgage servicing rights |  | $ 21 |  |  |  |
Gain on sale of mortgage servicing rights |  |  |  | 12 |  |
First Horizon Bank |  |  |  |  |  |
Mortgage Banking [Line Items] |  |  |  |  |  |
Net loans and leases | $ 40 |  |  | $ 40 |  |

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- Definition Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1402 -Subsection Instruction 3 + Details
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- Definition Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 + Details
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