Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Stockholders' Equity [Abstract]
Stock option exercises/stock unit conversions (shares)	442,054	1,875
Treasury stock, shares, acquired	469	0
Cash dividends declared on preferred stock, per share	$ 0.34	$ 0.34
Cash dividends declared on common stock, per share	$ 0.54	$ 0.53