Acquisition - Additional Information (Detail) - USD ($) $ in Thousands			12 Months Ended
	Apr. 30, 2014	Jan. 03, 2014	Dec. 31, 2016	Dec. 31, 2015	Apr. 30, 2015	Jan. 03, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill			$ 1,337,215	$ 1,332,348			$ 1,312,182
Other Acquisitions [Member]
Business Acquisition [Line Items]
Total consideration transferred at fair value			10,300	49,700
Business combination, historical carrying value of acquired deferred revenue				900
Acquired deferred revenue, impact on reported revenue			103	800
Deferred revenue				0
SpaceClaim Corporation [Member]
Business Acquisition [Line Items]
Total consideration transferred at fair value	$ 84,960
Business combination, historical carrying value of acquired deferred revenue	$ 3,300
Acquired deferred revenue, impact on reported revenue				600			2,000
Goodwill, period increase (decrease)					$ (4,800)
Deferred revenue			(700)
Goodwill			48,453
Reaction Design [Member]
Business Acquisition [Line Items]
Total consideration transferred at fair value		$ 19,100
Business combination, historical carrying value of acquired deferred revenue		$ 2,300
Acquired deferred revenue, impact on reported revenue				$ 300			$ 2,000
Goodwill, period increase (decrease)						$ 1,900
Deferred revenue			0
Finite-lived intangibles			7,000
Goodwill			$ 9,200
Noncontrolling interest, period decrease						$ (600)
Minimum [Member] | Reaction Design [Member]
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life			2 years
Maximum [Member] | Reaction Design [Member]
Business Acquisition [Line Items]
Finite-lived intangible asset, useful life			11 years