Condensed Consolidated Statements of Stockholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified		Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Deferred Compensation [Member]	Treasury Stock [Member]
Beginning Balances at Dec. 31, 2012		$ 256,598	$ 4,671	$ 150,750	$ 106,239	$ (5,062)	$ 982	$ (982)
Beginning Balances, shares at Dec. 31, 2012	[1]		14,396,248
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		32,787			32,787
Other comprehensive income		2,529				2,529
Dividend declared, shares			0
Dividend declared ($1.013 and $0.797 per share for 2013 and 2014 respectively)		(14,758)	0	(6)	(14,752)
Conversion of debentures, shares	[1]		26,074
Conversion of debentures		295	8	287
Share-based compensation, shares	[1],[2],[3]		35,022
Share-based compensation and tax benefit	[2],[3]	1,322	12	1,310
Treasury stock activities		0					142	(142)
Ending Balances at Dec. 31, 2013		278,773	4,691	152,341	124,274	(2,533)	1,124	(1,124)
Ending Balances, shares at Dec. 31, 2013	[1]		14,457,345
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		25,995			25,995
Other comprehensive income		64				64
Dividend declared, shares			18,078
Dividend declared ($1.013 and $0.797 per share for 2013 and 2014 respectively)		(10,920)	6	790	(11,716)
Retirement savings plan, shares			14,751
Retirement savings plan		602	5	597
Conversion of debentures, shares	[1]		47,313
Conversion of debentures		535	15	520
Share-based compensation, shares	[1],[2],[3]		40,158
Share-based compensation and tax benefit	[2],[3]	1,172	13	1,159
Stock Split in Form of Stock Dividend Adjustment to Retained Earnings		(2,365)	2,365		(2,365)
Treasury stock activities		0					93	(93)
Ending Balances at Sep. 30, 2014		$ 296,221	$ 7,095	$ 155,407	$ 136,188	$ (2,469)	$ 1,217	$ (1,217)
Ending Balances, shares at Sep. 30, 2014	[1]		14,577,645

[1] Includes 52,760 and 51,743 shares at September 30, 2014 and December 31, 2013, respectively, held in a Rabbi Trust related to our Non-Qualified Deferred Compensation Plan.

[2] Includes amounts for shares issued for Directors’ compensation.

[3] The shares issued under the SICP are net of shares withheld for employee taxes. For the nine months ended September 30, 2014 and for the year ended December 31, 2013, we withheld 12,687 and 15,617 shares, respectively, for taxes.