Business Combinations (Narrative) (Details) - USD ($)	3 Months Ended					12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2017	Dec. 31, 2016
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 51,223,000			$ 28,789,000		$ 51,223,000	$ 28,789,000
Goodwill arising from purchase						36,005,000	19,325,000
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	21,184,000			9,106,000		$ 21,184,000	$ 9,106,000
Economic useful lives of intangible assets						11 years	9 years
Technology, trademark and tradename
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	25,704,000			13,970,000		$ 25,704,000	$ 13,970,000
Economic useful lives of intangible assets						8 years	8 years
Patents
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 2,550,000			3,188,000		$ 2,550,000	$ 3,188,000
Economic useful lives of intangible assets						8 years	7 years
LDD
Acquired Finite-Lived Intangible Assets [Line Items]
Business combination, percentage of voting interests acquired	100.00%					100.00%
Total purchase price	$ 9,944,000
Contingent consideration	902,000
Escrow deposit	948,000					$ 948,000
Goodwill arising from purchase	4,690,000
LDD | Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 1,006,000					1,006,000
Economic useful lives of intangible assets	6 years
LDD | Technology, trademark and tradename
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 2,608,000					$ 2,608,000
Economic useful lives of intangible assets	6 years
ILT
Acquired Finite-Lived Intangible Assets [Line Items]
Business combination, percentage of voting interests acquired		100.00%
Total purchase price		$ 40,256,000
Goodwill arising from purchase		22,415,000
ILT | Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 11,660,000
Economic useful lives of intangible assets		13 years
ILT | Technology, trademark and tradename
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets		$ 7,480,000
Economic useful lives of intangible assets		8 years
OptiGrate
Acquired Finite-Lived Intangible Assets [Line Items]
Business combination, percentage of voting interests acquired			100.00%
Total purchase price			$ 16,870,000
Escrow deposit			1,849,000
Goodwill arising from purchase			8,900,000
OptiGrate | Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets			$ 1,010,000
Economic useful lives of intangible assets			4 years
OptiGrate | Technology, trademark and tradename
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets			$ 4,650,000
Economic useful lives of intangible assets			9 years
BSI
Acquired Finite-Lived Intangible Assets [Line Items]
Total purchase price				1,481,000
BSI | Patents
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets				$ 1,395,000			$ 1,395,000
Economic useful lives of intangible assets				7 years
Menara
Acquired Finite-Lived Intangible Assets [Line Items]
Total purchase price					$ 46,831,000
Goodwill arising from purchase					19,325,000
Goodwill, expected tax deductible amount					0
Menara | Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets					$ 9,500,000
Economic useful lives of intangible assets					10 years
Menara | Technology, trademark and tradename
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets					$ 9,900,000
Economic useful lives of intangible assets					7 years