Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Loan valuations and loss reserves	$ 108	$ 161
Employee benefits	93	83
Accrued expenses	22	16
Depreciation and amortization	24	13
Lease liability	91	94
Federal loss carryforwards	34	38
State loss carryforwards	2	2
Securities available-for-sale and financial instruments	355	12
Other	32	29
Gross deferred tax assets	761	448
Deferred tax liabilities:
Equity investments	3	4
Other intangible assets	80	86
Prepaid expenses	17	18
ROU lease asset	82	85
Leasing	265	198
Other	1	5
Gross deferred tax liabilities	448	396
Net deferred tax assets	$ 313	$ 52

Deferred Tax Assets, Lease Liability

No definition available.

Name:	fhn_DeferredTaxAssetsLeaseLiability
Namespace Prefix:	fhn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The tax effect as of the balance sheet date of the amount of the estimated future tax deductions arising from the provision for loan losses, which can only be deducted for tax purposes when actual loan losses are known, and which can only be realized if sufficient tax-basis income is generated in future periods to enable the deduction to be taken. Also includes losses associated with the repurchase obligations and other loss reserves.

+ References

No definition available.