Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - $ / shares	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Statement of Stockholders' Equity [Abstract]
Stock option exercises (shares)	67,075	171,474
Treasury stock, shares, acquired	0	140,571
Cash dividends declared on preferred stock, per share	$ 0.67	$ 0.67
Cash dividends declared on common stock, per share	$ 1.07	$ 1.04