CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net Income	$ 21,962	$ 31,549	$ 15,302
Other Comprehensive Income:
Unrealized Foreign Currency Translation Gain	95	(247)	111
Unrealized Holding Gain on Marketable Securities	(128)	(5)	133
Change in Fair Value of Derivatives	1,243	101	(1,856)
Change in Funding Status of Defined Benefit Plan	(2,209)	(5,998)	(3,495)
Comprehensive Income	$ 20,963	$ 25,400	$ 10,195