Consolidated Statements of Changes in Shareholders' Equity $ in Thousands	USD ($)
Total shareholders’ equity at beginning of period at Dec. 31, 2016	$ 3,002,528
Cumulative effect of accounting change at Dec. 31, 2016	0
Total shareholders' equity at beginning of period, as adjusted at Dec. 31, 2016	3,002,528
Net income	170,494
Other comprehensive income (loss)	75,933
Stock option exercises/stock unit conversions (428,599 shares in 2018 and 752,075 shares in 2017)	44,149
Stock compensation expense recognized in earnings	6,291
Purchase of treasury stock (601 shares in 2018 and 469 shares in 2017)	(42)
Cash dividends – preferred stock (approximately $0.67 per share in both 2018 and in 2017)	(4,031)
Cash dividends – common stock ($1.24 per share in 2018 and $1.11 per share in 2017)	(71,393)
Total shareholders’ equity at end of period at Jun. 30, 2017	3,223,929
Total shareholders’ equity at beginning of period at Dec. 31, 2017	3,297,863
Cumulative effect of accounting change at Dec. 31, 2017	(2,285)
Total shareholders' equity at beginning of period, as adjusted at Dec. 31, 2017	3,295,578
Net income	217,821
Other comprehensive income (loss)	(152,366)
Stock option exercises/stock unit conversions (428,599 shares in 2018 and 752,075 shares in 2017)	25,448
Stock compensation expense recognized in earnings	6,760
Purchase of treasury stock (601 shares in 2018 and 469 shares in 2017)	(70)
Cash dividends – preferred stock (approximately $0.67 per share in both 2018 and in 2017)	(4,031)
Cash dividends – common stock ($1.24 per share in 2018 and $1.11 per share in 2017)	(79,628)
Total shareholders’ equity at end of period at Jun. 30, 2018	$ 3,309,512