Consolidated Statements of Changes in Stockholder's Equity (Unaudited) (USD $) In Thousands, unless otherwise specified	Total	Preferred Equity	Common Stock	Surplus	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Beginning balance at Dec. 31, 2012	$ 2,936,399	$ 63,272	$ 1,750	$ 1,602,136	$ 1,281,811	$ 48,603	$ (61,173)
Comprehensive (loss) income:
Net income	95,276	0	0	0	95,276	0	0
Other comprehensive income (loss)	(73,618)	0	0	0	0	(73,618)	0
Comprehensive income (loss)	21,658
Common stock issued:
Stock-based compensation plans, net	3,995	0	0	387	(16,793)	0	20,401
Purchase of treasury stock	(63,239)	0	0	0	0	0	(63,239)
Cash dividends:
Common stock	(26,957)	0	0	0	(26,957)	0	0
Preferred stock	(2,600)	0	0	0	(2,600)	0	0
Issuance of preferred stock	0	0
Accretion of preferred stock discount	0	0	0	0	0	0	0
Purchase of preferred stock	0	0	0	0	0	0	0
Stock-based compensation expense, net	7,571	0	0	7,571	0	0	0
Tax benefit of stock options	149	0	0	149	0	0	0
Ending balance at Jun. 30, 2013	2,876,976	63,272	1,750	1,610,243	1,330,737	(25,015)	(104,011)
Beginning balance at Dec. 31, 2013	2,891,290	61,862	1,750	1,617,990	1,392,508	(24,244)	(158,576)
Comprehensive (loss) income:
Net income	91,564	0	0	0	91,564	0	0
Other comprehensive income (loss)	34,738	0	0	0	0	34,738	0
Comprehensive income (loss)	126,302
Common stock issued:
Stock-based compensation plans, net	8,363	0	0	1,071	(19,735)	0	27,027
Purchase of treasury stock	(72,647)	0	0	0	0	0	(72,647)
Cash dividends:
Common stock	(29,175)	0	0	0	(29,175)	0	0
Preferred stock	(2,522)	0	0	0	(2,522)	0	0
Purchase of preferred stock	(960)	(838)	0	0	(122)	0	0
Stock-based compensation expense, net	8,468	0	0	8,468	0	0	0
Tax benefit of stock options	827	0	0	827	0	0	0
Ending balance at Jun. 30, 2014	$ 2,929,946	$ 61,024	$ 1,750	$ 1,628,356	$ 1,432,518	$ 10,494	$ (204,196)