Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of tangible or intangible assets, including a business or subsidiary of the acquirer transferred by the entity to the former owners of the acquiree. Excludes cash.

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Acquisitions Fair Value of Consideration Transferred 2019 (Details) - USD ($) $ in Thousands			12 Months Ended
	Nov. 01, 2019	Feb. 01, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash			$ 815,591
Fair value of common stock issued as consideration in connection with acquisitions			307,173	$ 0	$ 0
Total consideration transferred at fair value			1,122,764
Livermore Software Technology Corporation
Cash	$ 470,623
Fair value of common stock issued as consideration in connection with acquisitions	307,173
Total consideration transferred at fair value	$ 777,796
Granta Design
Cash		$ 208,736
Total consideration transferred at fair value		$ 208,736
Other Acquisitions
Cash			136,232
Total consideration transferred at fair value			$ 136,232