CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (Unaudited) (USD $) In Thousands	Total	Common Stock Shares [Member]	Non-Redeemable Preferred Stock [Member]	Capital in Excess of Par Value [Member]	Retained Earnings [Member]	Treasury Stock-Common [Member]
Balance at Dec. 31, 2013	$ 411,715	$ 2,685	$ 3,000	$ 167,550	$ 266,854	$ (28,374)
Balance, shares at Dec. 31, 2013		26,846
Net income	22,754				22,754
Dividends paid on preferred stocks	(300)				(300)
Stock-based compensation	925			925
Exercise of stock options	510	6		504
Exercise of stock options, shares		60
Balance at Jun. 30, 2014	$ 435,604	$ 2,691	$ 3,000	$ 168,979	$ 289,308	$ (28,374)
Balance, shares at Jun. 30, 2014		26,906