Acquisitions (Narrative) (Details) $ in Thousands							12 Months Ended
	Jul. 19, 2017 USD ($)	Jan. 31, 2017 USD ($)	Jun. 17, 2015 USD ($)	Jun. 16, 2015 USD ($)	Apr. 02, 2015 USD ($)	Feb. 09, 2015 USD ($)	Dec. 31, 2017 item
Business Acquisition [Line Items]
Number of businesses acquired | item							0
Vertex-Global Holding B.V. [Member]
Business Acquisition [Line Items]
Acquired ownership percentage		100.00%
Acquisition date							Jan. 31, 2017
Fair value of consideration paid		$ 37,562
Cimatron [Member]
Business Acquisition [Line Items]
Acquired ownership percentage						100.00%
Acquisition date							Feb. 09, 2015
Consideration paid in cash						$ 77,984
Easyway [Member]
Business Acquisition [Line Items]
Acquired ownership percentage	5.00%				65.00%		70.00%
Acquisition date							Apr. 02, 2015
Consideration paid in cash					$ 11,265
Fair value of consideration paid	$ 2,300
STEAMtrax [Member]
Business Acquisition [Line Items]
Acquisition date							Jun. 16, 2015
Consideration paid in cash				$ 2,550
Noquo [Member]
Business Acquisition [Line Items]
Acquisition date							Jun. 17, 2015
Fair value of consideration paid			$ 651