Stock-based Compensation - ESPP (Details)	9 Months Ended
Sep. 30, 2021
2015 ESPP [Member]
Share-based compensation
Percentage related to employees to purchase shares at the lower fair market value at offering period	85.00%

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.

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