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Description of financial instruments, excluding certain derivatives, with off-balance sheet credit risk (for example, standby letters of credit or financial guarantees), including (1) information about the (shared) activity, region or economic characteristic that identifies the concentration, (2) the face or contract amount of the instrument, (3) the nature and terms of the instrument, including the market risk, cash requirements and accounting policies for it, (4) the maximum amount of loss due to credit risk that would be incurred if the counterparties failed completely to perform according to the terms of the contracts, and any security or collateral that proved to be of no value, (5) the entity's policy of requiring collateral or other security to support financial instruments subject to credit risk, information about access to collateral or other security, and a brief description of the security supporting those financial instruments, and (6) the policy of entering into and a brief description of master netting arrangements to mitigate the credit risk, and the extent to which such arrangements would reduce the maximum amount of loss due to credit risk.

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Summary of Significant Accounting Policies - Additional Information (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024 USD ($) Customer	Sep. 30, 2023 Customer	Sep. 30, 2024 USD ($) Customer	Sep. 30, 2023 Customer	Dec. 31, 2023 USD ($) Customer
Summary Of Significant Accounting Policies [Line Items]
Description of significant off-balance sheet risk			The Company has no significant off-balance sheet risk, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements.
Accounts receivable, net	$ 44,542,000		$ 44,542,000		$ 39,963,000
Car Offer
Summary Of Significant Accounting Policies [Line Items]
Goodwill and other asset additional impairment	0
Trade Accounts Receivable
Summary Of Significant Accounting Policies [Line Items]
Trade accounts receivable from receivables in transit, net of payables due, from the third-party payment processor	2,216,000		2,216,000		2,868,000
Receivables offset by payments received in advance	1,311,000		1,311,000		2,015,000
Accounts receivable, net	$ 905,000		$ 905,000		853,000
Sales Revenue, Net \| Customer Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Number of major customers \| Customer	0	0	0	0
Net Accounts Receivable \| Advertising Customers
Summary Of Significant Accounting Policies [Line Items]
Unbilled accounts receivable	$ 11,795,000		$ 11,795,000		$ 9,581,000
Net Accounts Receivable \| Customer Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Number of major customers \| Customer			0		0
Net Accounts Receivable \| Customer Concentration Risk \| Customer One
Summary Of Significant Accounting Policies [Line Items]
Concentration of credit risk, percentage			10.00%		10.00%
Minimum \| Net Accounts Receivable \| Customer Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Number of major customers \| Customer			1,000		1,000