v3.26.1
Business Segment Information - Narrative (Details)
3 Months Ended
Mar. 31, 2026
Segment Reporting [Abstract]
Number of reportable segments disclosed by definition flag
reportable business segment
X
- Definition
Number Of Reportable Segments Disclosed By Definition Flag
+ References
No definition available.
+ Details
Name:
fhn_NumberOfReportableSegmentsDisclosedByDefinitionFlag
Namespace Prefix:
fhn_
Data Type:
xbrli:stringItemType
Balance Type:
na
Period Type:
duration
X
- References
No definition available.
+ Details
Name:
us-gaap_SegmentReportingAbstract
Namespace Prefix:
us-gaap_
Data Type:
xbrli:stringItemType
Balance Type:
na
Period Type:
duration