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Fair Value Measurements (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | $ 905,798 | $ 935,844
Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 165,196 | 88,073
Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 740,602 | 847,771
Cash Equivalents |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 183,003 | 147,463
Cash Equivalents | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 165,196 | 88,073
Cash Equivalents | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 17,807 | 59,390
Short-Term Investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 651,213 | 725,063
Short-Term Investments | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 0 | 0
Short-Term Investments | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 651,213 | 725,063
Long Term Investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 71,582 | 63,318
Long Term Investments | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 0 | 0
Long Term Investments | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 71,582 | 63,318
Money market funds | Cash Equivalents |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 165,196 | 88,073
Money market funds | Cash Equivalents | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 165,196 | 88,073
Money market funds | Cash Equivalents | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 0 | 0
Commercial paper | Cash Equivalents |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 9,940 | 50,791
Commercial paper | Cash Equivalents | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 0 | 0
Commercial paper | Cash Equivalents | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 9,940 | 50,791
Commercial paper | Short-Term Investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 266,653 | 421,279
Commercial paper | Short-Term Investments | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 0 | 0
Commercial paper | Short-Term Investments | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 266,653 | 421,279
Municipal debt securities | Cash Equivalents |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 7,867 | 8,599
Municipal debt securities | Cash Equivalents | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 0 | 0
Municipal debt securities | Cash Equivalents | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Cash Equivalents | 7,867 | 8,599
Municipal debt securities | Short-Term Investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 12,738 | 30,426
Municipal debt securities | Short-Term Investments | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 0 | 0
Municipal debt securities | Short-Term Investments | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 12,738 | 30,426
Municipal debt securities | Long Term Investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 13,495 | 7,580
Municipal debt securities | Long Term Investments | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 0 |
Municipal debt securities | Long Term Investments | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 13,495 | 7,580
US Treasury Bonds |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 23,578 | 0
US Treasury Bonds | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 0 | 0
US Treasury Bonds | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 23,578 | 0
Corporate debt securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 27,093 | 35,688
Corporate debt securities | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 0 | 0
Corporate debt securities | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 27,093 | 35,688
Corporate debt securities | Short-Term Investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 151,610 | 166,136
Corporate debt securities | Short-Term Investments | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 0 | 0
Corporate debt securities | Short-Term Investments | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 151,610 | 166,136
Federal agency debt securities |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 30,994 | 20,050
Federal agency debt securities | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 0 | 0
Federal agency debt securities | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 30,994 | 20,050
Federal agency debt securities | Short-Term Investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 196,634 | 107,222
Federal agency debt securities | Short-Term Investments | Fair Value, Inputs, Level 1 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | 0 | 0
Federal agency debt securities | Short-Term Investments | Fair Value, Inputs, Level 2 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Debt Securities, Available-for-Sale | $ 196,634 | $ 107,222

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- Definition Amount 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 -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (aa) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479130/326-30-45-1 + 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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