Goodwill - Schedule of Changes in Goodwill (Detail) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | 12 Months Ended | |
|---|---|---|---|---|
Sep. 30, 2021 |
Sep. 30, 2021 |
Sep. 30, 2020 |
Dec. 31, 2020 |
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| Goodwill [Line Items] | ||||
| Balance, beginning of period before cumulative loss on impairment | $ 28,520 | $ 28,454 | $ 28,454 | |
| Accumulated loss on impairment | (4,763) | (4,456) | (4,456) | |
| Balance, beginning of period after cumulative loss on impairment | 23,757 | 23,998 | 23,998 | |
| Impairments based on the estimated fair value goodwill | $ 0 | 0 | $ (307) | (307) |
| Balance, end of period before cumulative loss on impairment | 28,749 | 28,749 | 28,520 | |
| Accumulated loss on impairment | (4,763) | (4,763) | (4,763) | |
| Ending period balance | $ 23,986 | 23,986 | 23,757 | |
| Radio Stations [Member] | ||||
| Goodwill [Line Items] | ||||
| Acquisitions | 4 | $ 66 | ||
| Digital Media [Member] | ||||
| Goodwill [Line Items] | ||||
| Acquisitions | $ 225 | |||
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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