CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Common stock - cash dividends declared per share (in dollars per share)	$ 0.56	$ 0.48	$ 0.36
Preferred stock - cash dividends declared per share (in dollars per share)	$ 6,200	$ 6,200	$ 6,200
First Horizon Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased under share repurchase programs	$ 129.9	$ 99.4

Aggregate dividends declared during the period for each share of common stock outstanding.

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