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Fair Value Measurements and Available for Sale Investments - Schedule of Unrealized Loss and Fair Values in a Loss Position (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
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Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 Months, Fair Value | $ 39,317 | $ 23,594
Less than 12 Months, Gross Unrealized Losses | (14) | (6)
12 Months or Greater, Fair Value | 0 | 0
12 Months or Greater, Gross Unrealized Losses | 0 | 0
Fair Value | 39,317 | 23,594
Gross Unrealized Losses | (14) | (6)
Agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 Months, Fair Value | 9,998 |
Less than 12 Months, Gross Unrealized Losses | (1) |
12 Months or Greater, Fair Value | 0 |
12 Months or Greater, Gross Unrealized Losses | 0 |
Fair Value | 9,998 |
Gross Unrealized Losses | (1) |
Commercial and corporate obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 Months, Fair Value | 4,096 | 5,986
Less than 12 Months, Gross Unrealized Losses | (3) | (4)
12 Months or Greater, Fair Value | 0 | 0
12 Months or Greater, Gross Unrealized Losses | 0 | 0
Fair Value | 4,096 | 5,986
Gross Unrealized Losses | (3) | (4)
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Less than 12 Months, Fair Value | 25,223 | 17,608
Less than 12 Months, Gross Unrealized Losses | (10) | (2)
12 Months or Greater, Fair Value | 0 | 0
12 Months or Greater, Gross Unrealized Losses | 0 | 0
Fair Value | 25,223 | 17,608
Gross Unrealized Losses | $ (10) | $ (2)

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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), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121590138&loc=SL82922954-210456 + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455 + Details
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