Accrued Liabilities (Schedule Of Accrued Liabilities) (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accrued Liabilities [Abstract]
Accrued salaries, bonus, and benefits	$ 1,376,613	$ 1,641,491
Accrued rent	348,690	441,417
Accrued licenses and maintenance fees	581,691	581,672
Accrued warranties	145,172	164,365	$ 222,845
Accrued taxes	258,964	234,668
Accrued professional services	491,894	367,072
Other	325,519	299,931
Total accrued liabilities	3,528,543	3,730,616
Less: Long term accrued liabilities	(580,866)	(535,369)
Total current accrued liabilities	$ 2,947,677	$ 3,195,247