Income Taxes (Schedule Of Effective Income Tax Rate Reconciliation) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Abstract]
Tax expense at statutory rate	$ 6,444,000	$ 1,995,000	$ 2,959,000
Non-Deductible transaction costs	908,000
State income taxes, net of federal benefit	531,000	499,000	220,000
Non-deductible loss on unit disposals	455,000
Non-deductible entertainment expenses	221,000	184,000	218,000
Equity compensation	135,000	144,000	63,000
Foreign income taxes	130,000	118,000	69,000
Provision to return adjustments	29,000	122,000	(321,000)
Non-deductible change in stock basis of subsidiary			(641,000)
Domestic production activities deduction	(456,000)	(87,000)	(153,000)
Research and development credit	(296,000)	(281,000)	(237,000)
Net change in uncertain tax positions	(153,000)	(869,000)	(781,000)
State valuation allowance adjustment	(84,000)	(19,000)	83,000
Other	(230,000)	57,000	(98,000)
Income tax expense	$ 7,634,000	$ 1,863,000	$ 1,381,000