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Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Apr. 09, 2012	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Caivis Group [Member]
Related Party Transaction [Line Items]
Repayments of debt				$ 533
Caivis Group [Member] \| Accounts Payable and Accrued Liabilities [Member]
Related Party Transaction [Line Items]
Due to related party		$ 0		0		$ 533
Caivis Group [Member] \| General Administrative And Corporate Development Support Activities [Member]
Related Party Transaction [Line Items]
Related party transaction fees payable per year	$ 2,000			0		0
Related party transaction fees	$ 2,000			0		0
Casting Made Simple Corp [Member] \| Websites Traffic Monetization Agreement [Member]
Related Party Transaction [Line Items]
Related party costs		49	$ 92	211	$ 277
Casting Made Simple Corp [Member] \| Websites Traffic Monetization Agreement [Member] \| Accounts Payable and Accrued Liabilities [Member]
Related Party Transaction [Line Items]
Due to related party		$ 48		$ 48		$ 70