Fair Value of Financial Instruments - Schedule of Fair Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Assets
Marketable securities	$ 403,264	$ 137,500
Commercial Paper
Assets
Marketable securities	375,699	113,622
Harvard
Liabilities
Success payment liability	42,600	35,500
Broad Institute
Liabilities
Success payment liability	42,800	35,700
Recurring \| Carrying Amount
Assets
Total assets	643,491	298,567
Liabilities
Total liabilities	122,959	71,200
Recurring \| Carrying Amount \| Money Market Funds
Assets
Cash equivalents	203,399	88,259
Recurring \| Carrying Amount \| Commercial Paper
Assets
Cash equivalents	7,498	60,494
Marketable securities	375,699	113,622
Recurring \| Carrying Amount \| Corporate Notes
Assets
Cash equivalents		12,314
Marketable securities	27,565	7,836
Recurring \| Carrying Amount \| Corporate Equity Securities
Assets
Equity securities included in other long-term investments	29,330
Recurring \| Carrying Amount \| Government Securities
Assets
Marketable securities		5,033
Recurring \| Carrying Amount \| U.S. Treasury Securities
Assets
Marketable securities		11,009
Recurring \| Carrying Amount \| Contingent Consideration of Technology Liabilities
Liabilities
Contingent consideration liability	30,348
Recurring \| Carrying Amount \| Contingent Consideration of Product Liabilities
Liabilities
Contingent consideration liability	7,211
Recurring \| Fair Value
Assets
Total assets	643,491	298,564
Liabilities
Total liabilities	122,959	71,200
Recurring \| Fair Value \| Money Market Funds
Assets
Cash equivalents	203,399	88,259
Recurring \| Fair Value \| Commercial Paper
Assets
Cash equivalents	7,498	60,497
Marketable securities	375,699	113,622
Recurring \| Fair Value \| Corporate Notes
Assets
Cash equivalents		12,308
Marketable securities	27,565	7,836
Recurring \| Fair Value \| Corporate Equity Securities
Assets
Equity securities included in other long-term investments	29,330
Recurring \| Fair Value \| Government Securities
Assets
Marketable securities		5,033
Recurring \| Fair Value \| U.S. Treasury Securities
Assets
Marketable securities		11,009
Recurring \| Fair Value \| Contingent Consideration of Technology Liabilities
Liabilities
Contingent consideration liability	30,348
Recurring \| Fair Value \| Contingent Consideration of Product Liabilities
Liabilities
Contingent consideration liability	7,211
Recurring \| Fair Value \| Level 1
Assets
Total assets	203,399	88,259
Recurring \| Fair Value \| Level 1 \| Money Market Funds
Assets
Cash equivalents	203,399	88,259
Recurring \| Fair Value \| Level 2
Assets
Total assets	440,092	210,305
Recurring \| Fair Value \| Level 2 \| Commercial Paper
Assets
Cash equivalents	7,498	60,497
Marketable securities	375,699	113,622
Recurring \| Fair Value \| Level 2 \| Corporate Notes
Assets
Cash equivalents		12,308
Marketable securities	27,565	7,836
Recurring \| Fair Value \| Level 2 \| Corporate Equity Securities
Assets
Equity securities included in other long-term investments	29,330
Recurring \| Fair Value \| Level 2 \| Government Securities
Assets
Marketable securities		5,033
Recurring \| Fair Value \| Level 2 \| U.S. Treasury Securities
Assets
Marketable securities		11,009
Recurring \| Fair Value \| Level 3
Liabilities
Total liabilities	122,959	71,200
Recurring \| Fair Value \| Level 3 \| Contingent Consideration of Technology Liabilities
Liabilities
Contingent consideration liability	30,348
Recurring \| Fair Value \| Level 3 \| Contingent Consideration of Product Liabilities
Liabilities
Contingent consideration liability	7,211
Recurring \| Harvard \| Carrying Amount
Liabilities
Success payment liability	42,600	35,500
Recurring \| Harvard \| Fair Value
Liabilities
Success payment liability	42,600	35,500
Recurring \| Harvard \| Fair Value \| Level 3
Liabilities
Success payment liability	42,600	35,500
Recurring \| Broad Institute \| Carrying Amount
Liabilities
Success payment liability	42,800	35,700
Recurring \| Broad Institute \| Fair Value
Liabilities
Success payment liability	42,800	35,700
Recurring \| Broad Institute \| Fair Value \| Level 3
Liabilities
Success payment liability	$ 42,800	$ 35,700

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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