Summary of Significant Accounting Policies - Additional Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 item segment	Mar. 31, 2020 USD ($)
Off Balance Sheet Risk and Concentrations of Credit Risk
Number of federally insured financial institutions \| item	2
Segment Information
Number of operating segments	1
Number of reporting segments	1
Revenue Recognition
Payment terms	45 days
Accounts receivable standard payment terms	45 days
Unrealized gains on marketable securities, reclassified from additional paid-in capital to accumulated other comprehensive income \| $		$ 63,000

Accounts receivable standard payment terms.

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- Definition

The number of federally insured financial institutions.

+ References

No definition available.

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- References

No definition available.

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- Definition

Payment terms in contract with customer. Includes, but is not limited to, timing of payment,

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No definition available.

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- Definition

Amount of unrealized holding gain (loss) on available-for-sale securities, reclassified from additional paid-in capital to accumulated other comprehensive income loss.

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No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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