Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Stockholders' Equity [Abstract]
Stock option exercises/stock unit conversions (shares)	66,215	100,865
Redemption of preferred stock (shares)	6,000,000	0
Treasury stock, shares, acquired	181,825	5,351
Approximate cash dividends declared on preferred stock, per share	$ 0.34	$ 0.34
Cash dividends declared on common stock, per share	$ 0.71	$ 0.67