XML 101 R82.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Loans - Troubled Debt Restructuring Narrative (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Troubled debt restructurings loans | $ 206.3 | $ 228.2
Allowance For TDRs To Recorded Investment Of TDRs |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Loan loss reserves | $ 19.7 | $ 27.7
Ratio of the allowance for loan losses to loans | 10.00% | 12.00%
Loans Held For Sale, Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Troubled debt restructurings loans | $ 51.1 | $ 57.8
Consumer | Consumer real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
TDRS maturities | 30 years |
Consumer | Permanent Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
TDR, reduction of interest rate by increment, basis points | 0.25% |
Modified interest rate increase | 1.00% |
TDRS maturities | 40 years |
Minimum | Consumer | Permanent Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Modified interest rate | 2.00% |
Modified interest rate time period | 5 years |
Minimum | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Forbearance agreements time period | 6 months |
Maximum | Consumer | Permanent Mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Modified interest rate time period | 5 years |
Maximum | Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Forbearance agreements time period | 12 months |
Heloc And Real Estate Installment Classes | Consumer | Consumer real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
TDR, reduction of interest rate by increment, basis points | 0.25% |
Modified interest rate increase | 2.00% |
Heloc And Real Estate Installment Classes | Minimum | Consumer | Consumer real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Modified interest rate | 1.00% |
Modified interest rate time period | 5 years |
Heloc And Real Estate Installment Classes | Maximum | Consumer | Consumer real estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Modified interest rate time period | 5 years |
Credit Card | Consumer | Credit Card and Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Credit card workout program, granted rate reduction | 0.00% |
Credit Card | Minimum | Consumer | Credit Card and Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Payment reductions, time period | 6 months |
Credit Card | Maximum | Consumer | Credit Card and Other |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Payment reductions, time period | 1 year |
Credit card workout program, term extension | 5 years |

X
- Definition Basis points increments used while modifying interest rates on TDRs. + References No definition available. + Details
Name: | fhn_BasisPointsIncrements
Namespace Prefix: | fhn_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Credit card workout program - Granted rate reduction, percentage, minimum. + References No definition available. + Details
Name: | fhn_CreditCardWorkoutProgramGrantedRateReduction
Namespace Prefix: | fhn_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Credit card workout program, maximum, term extension. + References No definition available. + Details
Name: | fhn_CreditCardWorkoutProgramTermExtension
Namespace Prefix: | fhn_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition TDRs are modified through forbearance agreements generally for 6 to 12 months. + References No definition available. + Details
Name: | fhn_ForbearanceAgreementsTimePeriod
Namespace Prefix: | fhn_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Modified Interest Rate, Minimum. + References No definition available. + Details
Name: | fhn_ModifiedInterestRate
Namespace Prefix: | fhn_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition After 5 years the interest rate steps up 1 percent every year thereafter until it reaches the Federal Home Loan Mortgage Corporation Weekly Survey Rate cap. + References No definition available. + Details
Name: | fhn_ModifiedInterestRateIncrease
Namespace Prefix: | fhn_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Modified Interest Rate Time Period, Maximum. + References No definition available. + Details
Name: | fhn_ModifiedInterestRateTimePeriod
Namespace Prefix: | fhn_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition For credit card hardship program, time range that payment reductions may be granted for modified loans classified as TDRs. + References No definition available. + Details
Name: | fhn_PaymentReductionsTimePeriod
Namespace Prefix: | fhn_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Ratio Of The Allowance For Loan Losses To Loans + References No definition available. + Details
Name: | fhn_RatioOfAllowanceForLoanLossesToLoans
Namespace Prefix: | fhn_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Maximum maturities for TDRs. + References No definition available. + Details
Name: | fhn_TdrMaturities
Namespace Prefix: | fhn_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of financing receivable modified as troubled debt restructuring. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554 + Details
Name: | us-gaap_FinancingReceivableModificationsRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=fhn_AllowanceForTdrsToRecordedInvestmentOfTdrsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=fhn_LoansHeldForSaleResidentialRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=fhn_ConsumerRealEstatePortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=fhn_PermanentMortgagePortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | fhn_SubClassofFinancingReceivableAxis=fhn_HelocAndRealEstateInstallmentClassesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | fhn_SubClassofFinancingReceivableAxis=fhn_CreditCardClassMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=fhn_CreditCardAndOtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |