Acquisitions - Additional Information (Details) - USD ($) $ in Thousands, shares in Millions	1 Months Ended				12 Months Ended
	Feb. 28, 2021	Sep. 30, 2020	Nov. 30, 2019	Feb. 28, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Goodwill					$ 140,627	$ 140,627
Estimated fair value of contingent consideration, short term liabilities					51,382
Estimated fair value of contingent consideration, long-term liabilities					102,361	121,901
Change in the estimated fair value of contingent consideration					31,842	52,793	$ 17,860
Oscine Corp | Stock Purchase Agreement
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired		100.00%
Business acquisition, consideration transferred		$ 8,500			8,500
Business acquisition, consideration transferred, cash		7,600
Business acquisition, consideration holdback amount		900
Oscine Corp | Stock Purchase Agreement | Maximum
Business Acquisition [Line Items]
Future milestone payments upon achievement of certain development and commercial milestones		$ 225,800
Cytocardia Inc.
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired			100.00%
Business acquisition, consideration transferred			$ 8,000				8,000
Business acquisition, consideration transferred, cash			6,800
Business acquisition, consideration holdback amount			1,200
Cytocardia Inc. | Maximum
Business Acquisition [Line Items]
Future milestone payments upon achievement of certain development and commercial milestones			$ 140,000
Cobalt Biomedicine Inc
Business Acquisition [Line Items]
Business acquisition, consideration transferred				$ 189,689
Business combination, intangible assets				59,195
Goodwill				140,627
Cobalt Biomedicine Inc | Acquisition Agreement
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired	100.00%
Business acquisition, shares restricted based on achievement of prespecified development milestone	12.1
Goodwill				140,600	140,600
Maximum success payment upon achievement of certain pre-specified development milestones				$ 500,000
Maximum period for success payment to achieve				20 years
Cobalt Biomedicine Inc | Acquisition Agreement | Research and Development Expense
Business Acquisition [Line Items]
Estimated fair value of success payment liability					88,300	64,700
Estimated fair value of contingent consideration					153,700	121,900
Estimated fair value of contingent consideration, short term liabilities					51,400
Estimated fair value of contingent consideration, long-term liabilities					102,300
(Gain) expense in connection with change in estimated fair value of success payment					23,600	62,300
Change in the estimated fair value of contingent consideration					$ 31,800	$ 52,800	$ 17,900
Cobalt Biomedicine Inc | Acquisition Agreement | Market Capitalization Equal to or Exceeds $8.1 billion
Business Acquisition [Line Items]
Cobalt success payment				$ 500,000
Cobalt Biomedicine Inc | Acquisition Agreement | IPR&D
Business Acquisition [Line Items]
Business combination, intangible assets				59,200
Cobalt Biomedicine Inc | Acquisition Agreement | RSAs
Business Acquisition [Line Items]
Business acquisition, RSAs and RSUs issued	0.7
Cobalt Biomedicine Inc | Acquisition Agreement | RSUs
Business Acquisition [Line Items]
Business acquisition, RSAs and RSUs issued	0.3
Cobalt Biomedicine Inc | Acquisition Agreement | A-2 Convertible Preferred Stock
Business Acquisition [Line Items]
Business acquisition, shares issued	36.4
Business acquisition, value of shares issued	$ 136,000
Cobalt Biomedicine Inc | Acquisition Agreement | Minimum
Business Acquisition [Line Items]
Threshold market capitalization				$ 8,100,000