Subsequent Events - Additional Information (Detail) - USD ($)	Feb. 11, 2019	Oct. 22, 2018
Subsequent Event [Line Items]
Maximum increase in new credit facilities aggregate amount		$ 25,000,000
Forrest-Pruzan Creative LLC [Member]
Subsequent Event [Line Items]
Equity method investment, ownership percentage	100.00%
New Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Line of credit		$ 50,000,000
Subsequent Event [Member] \| Forrest-Pruzan Creative LLC [Member]
Subsequent Event [Line Items]
Business acquisition, Name of acquired entity	Forrest-Pruzan Creative LLC
Cash consideration paid	$ 6,500,000
Business acquisition, working capital adjustments	1,500,000
Business acquisition, cash due after deferral period	2,000,000
Subsequent Event [Member] \| Forrest-Pruzan Creative LLC [Member] \| Class A Common Stock [Member]
Subsequent Event [Line Items]
Equity consideration paid	$ 2,200,000
Subsequent Event [Member] \| New Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Line of credit facility, amendment date	Feb. 11, 2019
Maximum increase in new credit facilities aggregate amount	$ 25,000,000
Line of credit	$ 75,000,000

Business acquisition cash due after deferral period.

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- Definition

Business acquisition working capital adjustment.

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- Definition

Line of credit facility, amendment date.

+ References

No definition available.

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- Definition

Maximum increase in new credit facilities aggregate amount.

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- Definition

Name of the acquired entity.

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- Definition

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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