Inventories And Warranties (Schedule Of Changes In Deferred Warranty Revenue) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Inventories And Warranties [Abstract]
Balance at beginning of period	$ 806	$ 787
Revenue deferrals	94	222
Amortization of deferred revenue	(214)	(223)
Total deferred warranty revenue	686	786
Current portion of deferred warranty revenue	(489)	(464)
Long-term deferred warranty revenue	$ 197	$ 322	$ 353