CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Stockholders' Equity [Abstract]
Common stock dividends (in dollars per share)	$ 1.20	$ 1.18	$ 1.10
Stock repurchased and retired (in shares)	12,768,949		11,446,197
Stock option plan (in shares)	26,063	15,080	20,888
Director stock purchase plan (in shares)		867
Employee stock purchase plan (in shares)	65,337	37,091	28,996
Restricted stock (in shares)	46,386	54,789	38,360
Repurchase of common stock (in shares)	(820,328)	(668,191)
Accounting Standards Update [Extensible List]	Adoption of ASC 326 - Financial Instruments - Credit Losses