Consolidated Statement of Changes in Stockholders' Equity (USD $) In Thousands, unless otherwise specified	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Loss
Balance at beginning of period at Dec. 31, 2014	$ 1,580,070	$ 129,796	$ 1,665	$ 897,049	$ 1,992,833	$ (1,375,322)	$ (65,951)
Increase (Decrease) in Stockholders' Equity
Net income	19,307				19,307
Other comprehensive income, net of tax	2,491						2,491
Dividends on preferred stock ($16.25 per share)	(2,194)				(2,194)
Dividends on common stock ($0.04 per share)	(3,995)				(3,995)
Sales of treasury stock (471,680 shares)	6,009				(3,739)	9,748
Restricted stock grants (26,232 shares)				(330)	(212)	542
Forfeitures of restricted stock (41,404 shares)				478	378	(856)
Stock-based compensation	1,608			1,597	11
Net tax benefit shortfall from stock-based compensation	(6)			(6)
Balance at end of period at Mar. 31, 2015	$ 1,603,290	$ 129,796	$ 1,665	$ 898,788	$ 2,002,389	$ (1,365,888)	$ (63,460)