XML 54 R40.htm IDEA: XBRL DOCUMENT
v3.22.2.2

Basis of Presentation and Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2022 | Feb. 27, 2022 | Dec. 31, 2021
Business Acquisition [Line Items] |  |  |  |
Common stock, par value (in dollars per share) | $ 0.625 | $ 0.625 |  | $ 0.625
TD Merger Agreement |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Additional cash to be received per common share upon closing, monthly basis (in dollars per share) |  |  | $ 0.054 |
Common stock, par value (in dollars per share) |  |  | 0.625 |
Cash to be received per common share upon closing (in dollars per share) |  |  | 25.00 |
Additional cash to be received per common share upon closing, annual basis (in dollars per share) |  |  | $ 0.65 |
Merger and integration expense | $ 21 | $ 55 |  |

X
- Definition Business Combination, Additional Cash To Be Received Per Common Share Upon Closing, Annual Basis + References No definition available. + Details
Name: | fhn_BusinessCombinationAdditionalCashToBeReceivedPerCommonShareUponClosingAnnualBasis
Namespace Prefix: | fhn_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Business Combination, Additional Cash To Be Received Per Common Share Upon Closing, Monthly Basis + References No definition available. + Details
Name: | fhn_BusinessCombinationAdditionalCashToBeReceivedPerCommonShareUponClosingMonthlyBasis
Namespace Prefix: | fhn_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Business Combination, Cash To Be Received Per Common Share Upon Closing + References No definition available. + Details
Name: | fhn_BusinessCombinationCashToBeReceivedPerCommonShareUponClosing
Namespace Prefix: | fhn_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- 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
Name: | us-gaap_BusinessAcquisitionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs. + References No definition available. + Details
Name: | us-gaap_BusinessCombinationIntegrationRelatedCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Face amount or stated value per share of common stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockParOrStatedValuePerShare
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=fhn_TDMergerAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |