CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Preferred Stock	Surplus	Retained earnings	Treasury Stock	Accumulated other comprehensive income (loss)
Beginning Balance at Dec. 31, 2016	$ 5,197,957	$ 1,040	$ 50,160	$ 4,255,022	$ 1,220,307	$ (8,286)	$ (320,286)
Net Income	209,835				209,835
Issuance of stock	5,515	2		5,513
Dividends declared:
Dividends, Common Stock, Cash	(76,620)				(76,620)
Dividends, Preferred Stock, Cash	(2,792)				(2,792)
Common stock purchases	(77,418)			4,518		(81,936)
Other comprehensive loss, net of tax	28,954						28,954
Ending Balance at Sep. 30, 2017	5,285,431	1,042	50,160	4,265,053	1,350,730	(90,222)	(291,332)
Cumulative effect of accounting change	1,935				1,935
Beginning Balance at Dec. 31, 2017	5,103,905	1,042	50,160	4,298,503	1,194,994	(90,142)	(350,652)
Net Income	511,755				511,755
Issuance of stock	2,565	1		2,564
Dividends declared:
Dividends, Common Stock, Cash	(76,200)				(76,200)
Dividends, Preferred Stock, Cash	(2,792)				(2,792)
Common stock purchases	(127,443)			(23,020)		(104,423)
Common stock reissuance	2,151			143		2,008
Stock based compensation	12,010			3,325		8,685
Other comprehensive loss, net of tax	(183,537)						(183,537)
Ending Balance at Sep. 30, 2018	$ 5,244,349	$ 1,043	$ 50,160	$ 4,281,515	$ 1,629,692	$ (183,872)	$ (534,189)