Acquisitions (2014 Acquisitions) (Narrative) (Details) - USD ($) $ in Thousands										12 Months Ended
	Dec. 17, 2014	Dec. 16, 2014	Nov. 25, 2014	Sep. 03, 2014	Aug. 28, 2014	Aug. 13, 2014	Aug. 06, 2014	Apr. 02, 2014	Feb. 18, 2014	Dec. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Acquisition date										Dec. 17, 2014
Consideration paid in cash	$ 54,552
Accrued earnouts and deferred payments related to acquisitions										$ 3,238	$ 159
Digital PlaySpace, Inc. [Member]
Business Acquisition [Line Items]
Acquisition date										Feb. 18, 2014
Fair value of consideration paid									$ 4,000
Consideration paid in cash									2,000
Consideration paid in shares									$ 2,000
Medical Modeling Inc. [Member]
Business Acquisition [Line Items]
Acquisition date										Apr. 02, 2014
Acquired ownership percentage								100.00%
Fair value of consideration paid								$ 69,026
Consideration paid in cash								51,526
Consideration paid in shares								$ 17,500
Laser Reproductions [Member]
Business Acquisition [Line Items]
Acquisition date										Aug. 06, 2014
Fair value of consideration paid							$ 17,450
Consideration paid in cash							13,075
Consideration paid in shares							$ 4,375
APM And APP [Member]
Business Acquisition [Line Items]
Acquisition date										Aug. 13, 2014
Consideration paid in cash						$ 14,089
Simbionix [Member]
Business Acquisition [Line Items]
Acquisition date										Aug. 28, 2014
Acquired ownership percentage					100.00%
Consideration paid in cash					$ 121,562
LayerWise [Member]
Business Acquisition [Line Items]
Acquisition date										Sep. 03, 2014
Acquired ownership percentage				100.00%
Consideration paid in cash				$ 41,933
Robtec [Member]
Business Acquisition [Line Items]
Acquisition date										Nov. 25, 2014
Acquired ownership percentage			70.00%							70.00%
Consideration paid in cash			$ 21,880
botObjects [Member]
Business Acquisition [Line Items]
Acquisition date										Dec. 16, 2014
Acquired ownership percentage		100.00%
Consideration paid in cash		$ 24,743
Additional earnout term		3 years
Maximum [Member] | botObjects [Member]
Business Acquisition [Line Items]
Accrued earnouts and deferred payments related to acquisitions		$ 25,000