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CASH, CASH EQUIVALENTS AND INVESTMENTS - Amortized Costs, Unrealized Gains and Losses, and Estimated Fair Value (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021
Total cash and equivalents |  |
Amortized Cost Basis | $ 136,628 | $ 1,179,297
Unrealized Gains | 1 | 0
Unrealized Losses | (2) | 0
Estimated Fair Value | 136,627 | 1,179,297
Short-term investments: |  |
Amortized Cost Basis | 1,045,464 | 0
Unrealized Gains | 362 | 0
Unrealized Losses | (108) | 0
Short-term investments | 1,045,718 | 0
Amortized Cost Basis | 1,182,092 | 1,179,297
Unrealized Gains | 363 | 0
Unrealized Losses | (110) | 0
Total cash, cash equivalents and short-term investments | 1,182,345 | 1,179,297
Debt securities, available-for-sale, realized gain | 300 |
Debt securities, available-for-sale, realized loss | 600 |
Interest and investment income | 19,800 |
U.S. agency securities |  |
Short-term investments: |  |
Amortized Cost Basis | 979,878 | 0
Unrealized Gains | 361 | 0
Unrealized Losses | (17) | 0
Short-term investments | 980,222 | 0
U.S. Treasury securities |  |
Short-term investments: |  |
Amortized Cost Basis | 65,586 | 0
Unrealized Gains | 1 | 0
Unrealized Losses | (91) | 0
Short-term investments | 65,496 | 0
Demand deposits |  |
Total cash and equivalents |  |
Amortized Cost Basis | 7,373 | 26,536
Estimated Fair Value | 7,373 | 26,536
Total cash equivalents |  |
Total cash and equivalents |  |
Amortized Cost Basis | 129,255 | 1,152,761
Unrealized Gains | 1 | 0
Unrealized Losses | (2) | 0
Estimated Fair Value | 129,254 | 1,152,761
Money market funds |  |
Total cash and equivalents |  |
Amortized Cost Basis | 64,855 | 1,152,761
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Estimated Fair Value | 64,855 | 1,152,761
U.S. agency securities |  |
Total cash and equivalents |  |
Amortized Cost Basis | 63,605 | 0
Unrealized Gains | 1 | 0
Unrealized Losses | (2) | 0
Estimated Fair Value | 63,604 | 0
U.S. Treasury securities |  |
Total cash and equivalents |  |
Amortized Cost Basis | 795 | 0
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Estimated Fair Value | $ 795 | $ 0

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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
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- Definition 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. + References No definition available. + Details
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- Definition Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(9)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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