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Summary of Significant Accounting Policies - Accounts Receivable and Current Expected Credit Losses and Concentration of Credit Risk and Deferred Revenue and Customer Deposits (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Customer One | Customer | Accounts Receivable
Concentration Risk [Line Items]
Concentration risk percentage	12.00%	11.00%

X

- Definition

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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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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