Goodwill And Intangible Assets (Summary Of Identifiable Intangible Assets) (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2018		Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Net Carrying Amount	$ 4,829		$ 5,613
Evolving Systems Labs And Evolving Systems NC, Inc [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	7,652	[1]	7,634
Accumulated Amortization	(2,823)	[2]	(2,021)	[3]
Net Carrying Amount	$ 4,829		$ 5,613
Weighted-Average Amortization Period	5 years 6 months		6 years 9 months 18 days
Evolving Systems Labs And Evolving Systems NC, Inc [Member] | Purchased Software [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 2,921		$ 2,921
Accumulated Amortization	(1,056)		(743)
Net Carrying Amount	$ 1,865		$ 2,178
Weighted-Average Amortization Period	4 years 10 months 24 days		7 years 8 months 12 days
Evolving Systems Labs And Evolving Systems NC, Inc [Member] | Trademarks And Tradenames [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 311		$ 310
Accumulated Amortization	(223)		(189)
Net Carrying Amount	$ 88		$ 121
Weighted-Average Amortization Period	2 years 4 months 24 days		3 years 8 months 12 days
Evolving Systems Labs And Evolving Systems NC, Inc [Member] | Non-competition [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 40		$ 40
Accumulated Amortization	(38)		(35)
Net Carrying Amount	$ 2		$ 5
Weighted-Average Amortization Period	7 months 6 days		2 years
Evolving Systems Labs And Evolving Systems NC, Inc [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 4,380		$ 4,363
Accumulated Amortization	(1,506)		(1,054)
Net Carrying Amount	$ 2,874		$ 3,309
Weighted-Average Amortization Period	6 years 1 month 6 days		8 years 8 months 12 days

[1] 2018 increase in gross amount due to measurement period adjustments relating to the EVOL BLS purchase price allocation. See Note 2 - Acquisitions for additional information.

[2] Includes functional currency adjustment of $69,000.

[3] Includes functional currency adjustment of $1,000.