XML 160 R138.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Derivatives - Derivatives Associated with Fixed Income Trading Activities (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Customer Interest Rate Contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | $ 2,271,448 | $ 2,026,753
Assets | 18,744 | 22,097
Liabilities | 27,768 | 18,323
Offsetting Upstream Interest Rate Contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 2,271,448 | 2,026,753
Assets | 4,014 | 17,931
Liabilities | 9,041 | 20,720
Option Contracts Purchased | Long |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 20,000 | 20,000
Assets | 25 | 15
Liabilities | 0 | 0
Forwards and Futures Purchased |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 4,684,177 | 6,257,140
Assets | 28,304 | 4,354
Liabilities | 181 | 5,526
Forwards and Futures Sold |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Notional | 4,967,454 | 6,292,012
Assets | 522 | 5,806
Liabilities | $ 30,055 | $ 4,010

X
- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
Name: | invest_DerivativeNotionalAmount
Namespace Prefix: | invest_
Data Type: | xbrli:monetaryItemType
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_DerivativeInstrumentsGainLossLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets. + References No definition available. + Details
Name: | us-gaap_InterestRateDerivativeAssetsAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities. + References No definition available. + Details
Name: | us-gaap_InterestRateDerivativeLiabilitiesAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=fhn_CustomerInterestRateContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=fhn_OffsettingUpstreamInterestRateContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_PutOptionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PositionAxis=us-gaap_LongMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=fhn_ForwardsAndFuturesPurchasedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=fhn_ForwardsAndFuturesSoldMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |