Consolidated Statements of Changes in Equity (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025		Dec. 31, 2024		Dec. 31, 2023
Equity, Class of Treasury Stock [Line Items]
Accounting Standards Update [Extensible List]					Accounting Standards Update 2023-02 [Member]
Common stock - cash dividends declared per share (in dollars per share)	$ 0.60		$ 0.60		$ 0.60
Common stock repurchased under share repurchase program	$ 918	[1]	$ 626	[1]	$ 10
General Purchase Plan
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased under share repurchase program	$ 894		$ 604

[1] 2025 and 2024 include $894 million and $604 million, respectively, repurchased under FHN's general purchase programs.