XML 158 R100.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Short-term Borrowings - Summary of Short-Term Borrowings (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Federal Funds Purchased |  |  |
Short-term Debt [Line Items] |  |  |
Average balance | $ 737,715 | $ 405,110 | $ 447,137
Year-end balance | 548,344 | 256,567 | 399,820
Maximum month-end outstanding | $ 1,281,853 | $ 503,138 | $ 568,490
Average rate for the year | 2.08% | 1.89% | 1.06%
Average rate at year-end | 1.55% | 2.50% | 1.48%
Securities Sold Under Agreements to Repurchase |  |  |
Short-term Debt [Line Items] |  |  |
Average balance | $ 701,164 | $ 713,841 | $ 578,666
Year-end balance | 716,925 | 762,592 | 656,602
Maximum month-end outstanding | $ 772,092 | $ 891,425 | $ 743,684
Average rate for the year | 1.89% | 1.40% | 0.72%
Average rate at year-end | 1.72% | 1.66% | 0.64%
Trading Liabilities |  |  |
Short-term Debt [Line Items] |  |  |
Average balance | $ 503,302 | $ 682,943 | $ 685,891
Year-end balance | 505,581 | 335,380 | 638,515
Maximum month-end outstanding | $ 754,220 | $ 890,717 | $ 896,943
Average rate for the year | 2.48% | 2.83% | 2.26%
Average rate at year-end | 2.07% | 3.21% | 2.22%
Other Short-term Borrowings |  |  |
Short-term Debt [Line Items] |  |  |
Average balance | $ 538,249 | $ 1,046,585 | $ 554,502
Year-end balance | 2,253,045 | 114,764 | 2,626,213
Maximum month-end outstanding | $ 2,276,139 | $ 2,229,155 | $ 2,626,213
Average rate for the year | 2.34% | 1.82% | 1.28%
Average rate at year-end | 2.14% | 2.48% | 1.44%

X
- Definition Short Term Debt Average Outstanding Rate + References No definition available. + Details
Name: | fhn_ShortTermDebtAverageOutstandingRate
Namespace Prefix: | fhn_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. + 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(19)(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(1)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(13)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
Name: | us-gaap_ShortTermBorrowings
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_ShortTermDebtLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average interest rate of short-term debt outstanding calculated at point in time. + 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 210.5-02.19(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_ShortTermDebtWeightedAverageInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period. + References No definition available. + Details
Name: | us-gaap_ShorttermDebtAverageOutstandingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, maximum month-end borrowings during the period. + 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(19)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_ShorttermDebtMaximumMonthendOutstandingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_ShortTermDebtTypeAxis=us-gaap_FederalFundsPurchasedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortTermDebtTypeAxis=us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortTermDebtTypeAxis=us-gaap_TradingLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortTermDebtTypeAxis=fhn_OtherShortTermBorrowingsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |