Investments and Fair Value Measurements - Schedule of Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Losses	$ (10)	$ (176)
Fair Value	49,499	201,181
U.S. treasury
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Losses	(1)	0
Fair Value	12,926	637
U.S. agency securities
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Losses	(9)	(111)
Fair Value	36,322	153,212
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Losses	0	(4)
Fair Value	0	6,086
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Losses	0	(61)
Fair Value	$ 251	$ 41,246

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 less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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=118955579&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=118939692&loc=d3e27337-111563

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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 unrealized loss position, 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 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922888-210455

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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