Quarterly report pursuant to Section 13 or 15(d)

FAIR VALUE MEASUREMENTS - Assets measured on recurring basis (Details)

v3.21.2
FAIR VALUE MEASUREMENTS - Assets measured on recurring basis (Details) - USD ($)
 1 Months Ended 3 Months Ended 9 Months Ended
Jun. 30, 2021
Sep. 30, 2021
Sep. 30, 2021
Sep. 30, 2020
Dec. 31, 2020
Assets          
Level 1 to Level 2 transfer   $ 0 $ 0 $ 0  
Level 2 to Level 1 transfer   0 0 0  
Transfer into Level 3     0 0  
Transfer out of Level 3     0 $ 0  
Net unrealized loss on equity investment   1,900,000 1,880,000    
Change in fair value of warrant liabilities     56,576,000    
Change in fair value of contingent consideration   200,000 166,000    
Interest and Other (Expense) Income , Net          
Assets          
Recognized gains on convertible debt instruments   100,000 600,000    
Subscription Agreement          
Assets          
Subscription liability $ 500,000 2,400,000      
Private Placement Warrants          
Assets          
Change in fair value of warrant liabilities   0 56,600,000    
Level 3          
Movement in Level 3 assets measured at fair value          
Balance at beginning of year     3,000,000    
Additions     23,620,000    
Changes in fair value     (4,161,000)    
Balance at end of year   22,459,000 22,459,000    
Movement in Level 3 liabilities measured at fair value          
Balance at beginning of period     93,328,000    
Additions     6,558,000    
Changes in fair value     59,022,000    
Foreign currency translation     (167,000)    
Exercise of private placement warrants     (149,904,000)    
Disposals     (2,920,000)    
Balance at end of period   5,917,000 5,917,000    
Recurring          
Assets          
Total assets   425,947,000 425,947,000   $ 597,753,000
Total liabilities   5,917,000 5,917,000   93,328,000
Recurring | Contingent Consideration          
Assets          
Total liabilities   5,917,000 5,917,000    
Recurring | Private Placement Warrants          
Assets          
Total liabilities         93,328,000
Recurring | Money market funds          
Assets          
Total assets   126,086,000 126,086,000   407,512,000
Recurring | Commercial paper          
Assets          
Total assets   128,825,000 128,825,000   119,285,000
Recurring | Corporate bonds          
Assets          
Total assets   86,899,000 86,899,000   47,959,000
Recurring | Government bonds          
Assets          
Total assets   36,520,000 36,520,000    
Recurring | Assetbacked securities          
Assets          
Total assets   24,828,000 24,828,000    
Recurring | Equity securities          
Assets          
Total assets   15,200,000 15,200,000    
Recurring | Company-owned life insurance cash surrender value          
Assets          
Total assets   330,000 330,000    
Recurring | Other investments          
Assets          
Total assets   7,259,000 7,259,000   3,000,000
Recurring | U.S Treasury securities          
Assets          
Total assets         19,997,000
Recurring | Level 1          
Assets          
Total assets   126,086,000 126,086,000   427,509,000
Recurring | Level 1 | Money market funds          
Assets          
Total assets   126,086,000 126,086,000   407,512,000
Recurring | Level 1 | U.S Treasury securities          
Assets          
Total assets         19,997,000
Recurring | Level 2          
Assets          
Total assets   277,402,000 277,402,000   167,244,000
Recurring | Level 2 | Commercial paper          
Assets          
Total assets   128,825,000 128,825,000   119,285,000
Recurring | Level 2 | Corporate bonds          
Assets          
Total assets   86,899,000 86,899,000   47,959,000
Recurring | Level 2 | Government bonds          
Assets          
Total assets   36,520,000 36,520,000    
Recurring | Level 2 | Assetbacked securities          
Assets          
Total assets   24,828,000 24,828,000    
Recurring | Level 2 | Company-owned life insurance cash surrender value          
Assets          
Total assets   330,000 330,000    
Recurring | Level 3          
Assets          
Total assets   22,459,000 22,459,000   3,000,000
Total liabilities   5,917,000 5,917,000   93,328,000
Recurring | Level 3 | Contingent Consideration          
Assets          
Total liabilities   5,917,000 5,917,000    
Recurring | Level 3 | Private Placement Warrants          
Assets          
Total liabilities         93,328,000
Recurring | Level 3 | Equity securities          
Assets          
Total assets   15,200,000 15,200,000    
Recurring | Level 3 | Other investments          
Assets          
Total assets   $ 7,259,000 $ 7,259,000   $ 3,000,000