Shareholders' Equity (Statement of Equity) (Details) (USD $)	3 Months Ended						9 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Sep. 30, 2012	Sep. 30, 2011
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			$ 155,327,000				$ 155,327,000
Net income	2,553,000			1,311,000			8,861,000	7,004,000
Other comprehensive income (loss), net of tax	1,008,000			(2,053,000)			(878,000)	4,000
Exercise of stock options (in shares)							109,111
Exercise of stock options							1,200,000
Tax impact on stock awards							(33,000)
Issuance of restricted common stock for services (in shares)	4,645	4,303	4,715	4,215	3,990	4,044
Issuance of restricted common stock for services	75,000	70,000	75,000	62,000	75,000	75,000	220,000
Issuance of common stock under Employee Stock Purchase Plan (in shares)							31,876	33,265
Issuance of common stock under Employee Stock Purchase Plan							445,000
Compensation cost of stock options							1,168,000
Balance	166,310,000						166,310,000
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance (in shares)			13,153,000				13,153,000
Balance			132,000				132,000
Exercise of stock options (in shares)							109,000
Exercise of stock options							1,000
Issuance of restricted common stock for services (in shares)							14,000
Issuance of common stock under Employee Stock Purchase Plan (in shares)							32,000
Balance (in shares)	13,308,000						13,308,000
Balance	133,000						133,000
Additional Paid-In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			60,565,000				60,565,000
Exercise of stock options							1,199,000
Tax impact on stock awards							(33,000)
Issuance of restricted common stock for services							220,000
Issuance of common stock under Employee Stock Purchase Plan							445,000
Compensation cost of stock options							1,168,000
Balance	63,564,000						63,564,000
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			98,902,000				98,902,000
Net income							8,861,000
Balance	107,763,000						107,763,000
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			(4,272,000)				(4,272,000)
Other comprehensive income (loss), net of tax							(878,000)
Balance	$ (5,150,000)						$ (5,150,000)