Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail)		3 Months Ended	12 Months Ended
		Mar. 31, 2022	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Jan. 31, 2023 robux	Jan. 31, 2022 robux	Jan. 30, 2022 robux
Disaggregation of Revenue [Line Items]
Average lifetime of a paying user			28 months	28 months	23 months
Decrease in revenue			$ 2,799,274,000	$ 2,225,052,000	$ 1,919,181,000
Cost of revenue	[1]		649,115,000	547,658,000	496,870,000
Developer exchange program, minimum virtual currency earned requirement | robux						30,000	50,000	100,000
Restricted cash			$ 0	0
Payment remittance term (within)			30 days
Intangible asset, useful life (up to)			3 years 2 months 12 days
Advertising cost			$ 38,300,000	$ 36,200,000	$ 26,800,000
Operating lease, renewal term (up to)			5 years
RSUs outstanding
Disaggregation of Revenue [Line Items]
Vesting period			4 years
One Distribution Channel | Accounts Receivable | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of revenue			30.00%	37.00%
One Distribution Channel | Revenue Benchmark | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of revenue			30.00%	32.00%	35.00%
Second Distribution Channel | Accounts Receivable | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of revenue			26.00%	19.00%
Second Distribution Channel | Revenue Benchmark | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Percentage of revenue			17.00%	18.00%	19.00%
Maximum
Disaggregation of Revenue [Line Items]
Average lifetime of a paying user		25 months
Intangible asset, useful life (up to)			5 years
Operating lease term			12 years
Minimum
Disaggregation of Revenue [Line Items]
Average lifetime of a paying user		23 months
Service Life
Disaggregation of Revenue [Line Items]
Decrease in revenue				$ (344,900,000)
Cost of revenue				$ (79,300,000)

[1] Depreciation of servers and infrastructure equipment included in infrastructure and trust & safety.