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