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Fair Value of Financial Instruments - Schedule of Estimated Fair Values of Financial Instruments Outstanding (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Cost | $ 12,220 | $ 18,104
Unrealized Gains | 0 | 0
Unrealized Losses | (37) | (16)
Fair Value | 12,183 | 18,088
Cash and Cash Equivalents |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 3,791 | 5,893
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Fair Value | 3,791 | 5,893
Short-term investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 6,001 | 9,276
Unrealized Gains | 0 | 0
Unrealized Losses | (8) | (9)
Fair Value | 5,993 | 9,267
Long-term investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 2,428 | 2,935
Unrealized Gains | 0 | 0
Unrealized Losses | (29) | (7)
Fair Value | $ 2,399 | $ 2,928

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- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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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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