| Assets and Liabilities Measured at Fair Value on a Recurring Basis | Assets and liabilities measured at fair value on a recurring basis as of June 30, 2022 are as follows:  
 
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| (in thousands) |  | Level 1 |  | Level 2 |  | Level 3 |  | Total |  
| Assets: |  |  |  |  |  |  |  |  |  
| Cash equivalents: |  |  |  |  |  |  |  |  |  
| Money market funds |  | $ | 30,141 |  |  | $ | — |  |  | $ | — |  |  | $ | 30,141 |  |  
|  |  |  |  |  |  |  |  |  |  
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| Short-term investments: |  |  |  |  |  |  |  |  |  
| Money market funds |  | 81 |  |  | — |  |  | — |  |  | 81 |  |  
| Mutual fund shares |  | 1,027 |  |  | — |  |  | — |  |  | 1,027 |  |  
| Other current assets: |  |  |  |  |  |  |  |  |  
| Derivative financial instruments |  | — |  |  | 22,297 |  |  | — |  |  | 22,297 |  |  
| Non-current assets: |  |  |  |  |  |  |  |  |  
| Money market funds |  | 1,208 |  |  | — |  |  | — |  |  | 1,208 |  |  
| Mutual fund shares |  | 17,826 |  |  | — |  |  | — |  |  | 17,826 |  |  
| Derivative financial instruments |  | — |  |  | 13,158 |  |  | — |  |  | 13,158 |  |  
| Total assets measured at fair value |  | $ | 50,283 |  |  | $ | 35,455 |  |  | $ | — |  |  | $ | 85,738 |  |  
| Liabilities: |  |  |  |  |  |  |  |  |  
| Accrued liabilities: |  |  |  |  |  |  |  |  |  
| Derivative financial instruments |  | $ | — |  |  | $ | 1,854 |  |  | $ | — |  |  | $ | 1,854 |  |  
| Other long-term liabilities: |  |  |  |  |  |  |  |  |  
| Derivative financial instruments |  | — |  |  | 261 |  |  | — |  |  | 261 |  |  
| Total liabilities measured at fair value |  | $ | — |  |  | $ | 2,115 |  |  | $ | — |  |  | $ | 2,115 |  |  | Assets and liabilities measured at fair value on a recurring basis as of December 31, 2021 are as follows:  
 
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
| (in thousands) |  | Level 1 |  | Level 2 |  | Level 3 |  | Total |  
| Assets: |  |  |  |  |  |  |  |  |  
| Cash equivalents: |  |  |  |  |  |  |  |  |  
| Money market funds |  | $ | 2,677 |  |  | $ | — |  |  | $ | — |  |  | $ | 2,677 |  |  
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| 
Available-for-sale short-term investments:(1)
 |  |  |  |  |  |  |  |  |  
| U.S. Government treasury bills |  | — |  |  | 130,168 |  |  | — |  |  | 130,168 |  |  
| Other short-term investments: |  |  |  |  |  |  |  |  |  
| Money market funds |  | 73 |  |  | — |  |  | — |  |  | 73 |  |  
| Mutual fund shares |  | 904 |  |  | — |  |  | — |  |  | 904 |  |  
| Other current assets: |  |  |  |  |  |  |  |  |  
| Derivative financial instruments |  | — |  |  | 9,397 |  |  | — |  |  | 9,397 |  |  
| Non-current assets: |  |  |  |  |  |  |  |  |  
| Money market funds |  | 2,219 |  |  | — |  |  | — |  |  | 2,219 |  |  
| Mutual fund shares |  | 19,606 |  |  | — |  |  | — |  |  | 19,606 |  |  
| Derivative financial instruments |  | — |  |  | 10,142 |  |  | — |  |  | 10,142 |  |  
| Total assets measured at fair value |  | $ | 25,479 |  |  | $ | 149,707 |  |  | $ | — |  |  | $ | 175,186 |  |  
| Liabilities: |  |  |  |  |  |  |  |  |  
| Accrued liabilities: |  |  |  |  |  |  |  |  |  
| Derivative financial instruments |  | $ | — |  |  | $ | 3,572 |  |  | $ | — |  |  | $ | 3,572 |  |  
| Other long-term liabilities: |  |  |  |  |  |  |  |  |  
| Derivative financial instruments |  | — |  |  | 318 |  |  | — |  |  | 318 |  |  
| Total liabilities measured at fair value |  | $ | — |  |  | $ | 3,890 |  |  | $ | — |  |  | $ | 3,890 |  | 
(1) Available-for-sale short-term investments have remaining maturities of less than one year.
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