Consolidated Statement of Changes in Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash dividends per share	$ 1.37	$ 1.36	$ 1.33
Grant of restricted stock, shares	126,427	97,004	90,075
Common stock options exercised, shares	128,742	72,296
Common Stock [Member]
Cash dividends per share	$ 1.37	$ 1.36	$ 1.33
Grant of restricted stock, shares	126,427	97,004	90,075
Forfeiture of restricted stock, shares	4,149	5,636	840
Common stock options exercised, shares	128,742	72,296	220,905
Acquisition, Shares			23,690,589
Treasury Stock [Member]
Purchase of treasury stock, shares	1,020,864	2,880,855	86
Deferred Compensation Plan [Member] | Treasury Stock [Member]
Distribution of treasury stock for deferred compensation plan, shares	27	31	31
Cardinal Financial Corporation [Member] | Common Stock [Member]
Acquisition, Shares			23,690,589