v3.20.4
Financial Instruments - Schedule of Financial Instruments, Measured at Fair Value on a Recurring and Non-recurring Basis (Details) - USD ($)
$ in Thousands
Dec. 31, 2020
Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents $ 2,703,597 $ 649,916
Marketable securities 3,684,370 1,805,278
Carrying Amount | Level 1 | Foreign exchange forward contracts    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets 0 0
Carrying Amount | Level 1 | U.S. federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 174,397  
Marketable securities 1,224,052 222,713
Carrying Amount | Level 1 | Corporate bonds and commercial paper    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 134,056  
Marketable securities 0 0
Carrying Amount | Level 1 | U.S. term deposits    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 885,000 300,000
Carrying Amount | Level 1 | Canadian federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 24,988 69,922
Carrying Amount | Level 1 | Repurchase agreements    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0 0
Carrying Amount | Level 2 | Foreign exchange forward contracts    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets 16,340 5,830
Carrying Amount | Level 2 | U.S. federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0  
Marketable securities 0 0
Carrying Amount | Level 2 | Corporate bonds and commercial paper    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0  
Marketable securities 1,550,330 1,212,643
Carrying Amount | Level 2 | U.S. term deposits    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 0 0
Carrying Amount | Level 2 | Canadian federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 0 0
Carrying Amount | Level 2 | Repurchase agreements    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 290,000 200,000
Carrying Amount | Level 3 | Foreign exchange forward contracts    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets 0 0
Carrying Amount | Level 3 | U.S. federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0  
Marketable securities 0 0
Carrying Amount | Level 3 | Corporate bonds and commercial paper    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0  
Marketable securities 0 0
Carrying Amount | Level 3 | U.S. term deposits    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 0 0
Carrying Amount | Level 3 | Canadian federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 0 0
Carrying Amount | Level 3 | Repurchase agreements    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0 0
Fair Value | Level 1 | Foreign exchange forward contracts    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets 0 0
Fair Value | Level 1 | U.S. federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 174,399  
Marketable securities 1,226,657 223,403
Fair Value | Level 1 | Corporate bonds and commercial paper    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 134,396  
Marketable securities 0 0
Fair Value | Level 1 | U.S. term deposits    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 887,102 301,354
Fair Value | Level 1 | Canadian federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 24,987 69,919
Fair Value | Level 1 | Repurchase agreements    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0 0
Fair Value | Level 2 | Foreign exchange forward contracts    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets 16,340 5,830
Fair Value | Level 2 | U.S. federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0  
Marketable securities 0 0
Fair Value | Level 2 | Corporate bonds and commercial paper    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0  
Marketable securities 1,552,907 1,216,822
Fair Value | Level 2 | U.S. term deposits    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 0 0
Fair Value | Level 2 | Canadian federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 0 0
Fair Value | Level 2 | Repurchase agreements    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 290,001 200,009
Fair Value | Level 3 | Foreign exchange forward contracts    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative assets 0 0
Fair Value | Level 3 | U.S. federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0  
Marketable securities 0 0
Fair Value | Level 3 | Corporate bonds and commercial paper    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0  
Marketable securities 0 0
Fair Value | Level 3 | U.S. term deposits    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 0 0
Fair Value | Level 3 | Canadian federal bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Marketable securities 0 0
Fair Value | Level 3 | Repurchase agreements    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents $ 0 $ 0