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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Acquisitions - Semma Therapeutics - Additional Information (Details) - USD ($)	Oct. 10, 2019	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Intangible asset		$ 400,000,000.0	$ 0
Semma Therapeutics, Inc.
Business Acquisition [Line Items]
Total purchase price	$ 936,764,000
Pre-Clinical Treatments For Device-Assisted Cells \| Semma Therapeutics, Inc.
Business Acquisition [Line Items]
Intangible asset	379,000,000.0
Naked Islets \| Semma Therapeutics, Inc.
Business Acquisition [Line Items]
Intangible asset	$ 8,000,000.0