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Concentration and Risks - Additional Information (Detail) - Revenue Benchmark [Member]	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Customer concentration risk [Member]
Concentration Risk [Line Items]
Concentration risk number of customers	0	0
Concentration risk percentage	10.00%	10.00%
Instructor concentration risk [Member] | Learning services and products [Member]
Concentration Risk [Line Items]
Concentration risk number of instructors	2	1
Concentration risk percentage	10.00%	10.00%

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- Definition

Concentration risk number of customers.

+ References

No definition available.

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- Definition

Concentration risk number of instructors.

+ References

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- 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.

+ Details

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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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-Publisher FASB
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