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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Section 1402
-Paragraph b
-Subparagraph (1)
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 210
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Mortgage Banking Activity - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss, excluding accrued interest	$ 709	$ 814	$ 709	$ 814	$ 730	$ 738	$ 822	$ 815
Net loans and leases	64,621		64,621			63,418
Mortgage banking income	9	$ 10	18	18
First Horizon Bank
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net loans and leases	25		25
Mortgage loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit loss, excluding accrued interest	$ 12		12			$ 12
Mortgage banking income			$ 1	$ 2