v3.10.0.1

INTANGIBLE ASSETS AND GOODWILL (Details) $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Jun. 30, 2018 number | Jun. 30, 2017 number | Jun. 30, 2018 USD ($) number | Sep. 30, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Changes in Intangible assets [Line Items] |  |  |  |  |  |
Goodwill |  |  |  | $ 871,454 | $ 862,000 |
Market approach for step one goodwill analysis [Abstract] |  |  |  |  |  |
Income model years used for the discounted cash flow approach | number |  |  | 10 |  |  |
Broadcasting License Impairment Testing [Member] |  |  |  |  |  |
Estimates and assumptions used for impairment test [Line Items] |  |  |  |  |  |
Discount rates | 9.00% | 9.25% |  |  |  |
Broadcasting License Impairment Testing [Member] | Maximum [Member] |  |  |  |  |  |
Estimates and assumptions used for impairment test [Line Items] |  |  |  |  |  |
Operating profit margin ranges of the markets of the Company | 37.00% | 40.00% |  |  |  |
Long-term revenue growth rate ranges of the markets of the Company | 1.00% | 2.00% |  |  |  |
Broadcasting License Impairment Testing [Member] | Minimum [Member] |  |  |  |  |  |
Estimates and assumptions used for impairment test [Line Items] |  |  |  |  |  |
Operating profit margin ranges of the markets of the Company | 22.00% | 19.00% |  |  |  |
Long-term revenue growth rate ranges of the markets of the Company | 0.50% | 1.00% |  |  |  |
Goodwill Impairment Testing [Member] |  |  |  |  |  |
Estimates and assumptions used for impairment test [Line Items] |  |  |  |  |  |
Discount rates | 9.00% | 9.25% |  |  |  |
Goodwill Impairment Testing [Member] | Maximum [Member] |  |  |  |  |  |
Estimates and assumptions used for impairment test [Line Items] |  |  |  |  |  |
Long-term revenue growth rate ranges of the markets of the Company | 1.00% | 2.00% |  |  |  |
Market approach for step one goodwill analysis [Abstract] |  |  |  |  |  |
Estimates of market multiples | number | 0 | 8 |  |  |  |
Goodwill Impairment Testing [Member] | Minimum [Member] |  |  |  |  |  |
Estimates and assumptions used for impairment test [Line Items] |  |  |  |  |  |
Long-term revenue growth rate ranges of the markets of the Company | 1.00% | 1.00% |  |  |  |
Market approach for step one goodwill analysis [Abstract] |  |  |  |  |  |
Estimates of market multiples | number | 0 | 7.5 |  |  |  |
Radio Broadcasting Licences [Member] |  |  |  |  |  |
Changes in Intangible assets [Line Items] |  |  |  |  |  |
Beginning of period balance |  |  | $ 2,649,959 | 2,649,959 | 823,195 |
Dispositions |  |  |  | 0 | (13,500) |
Consolidation of a VIE |  |  |  | 0 | (15,738) |
Acquisition of radio stations |  |  |  | 0 | 17,174 |
Acquisition of radio stations - CBS Radio Merger |  |  |  | 0 | 1,880,400 |
Disposition of Licenses - EMF Sale |  |  |  | 0 | (54,661) |
Acqusition of radio Stations - Beasley Transaction |  |  |  | 0 | 35,944 |
Acquisition of radio stations - iHeartMedia Transaction |  |  |  | 0 | 50,621 |
Disposition of radio stations - iHeartMedia Transaction |  |  |  | 0 | (7,462) |
Assets held for sale |  |  |  | 0 | (66,014) |
Acquisition of radio stations - Emmis Acquisition |  |  |  | 12,785 | 0 |
Acquisition Of Radio Station - Jerry Lee Acquisition |  |  |  | 27,346 | 0 |
Impairment loss |  |  |  | (702) | 0 |
Disposition Of Radio Stations -WXTU Transaction |  |  |  | (25,607) | 0 |
Ending period balance |  |  |  | 2,663,781 | 2,649,959 |
Goodwill [Member] |  |  |  |  |  |
Changes in Intangible assets [Line Items] |  |  |  |  |  |
Goodwill before cumulative loss on impairment |  |  |  |  | 988,056 | $ 158,333
Accumulated loss on impairment |  |  |  |  | (126,056) | (125,615)
Goodwill |  |  |  | 871,454 | 862,000 | $ 32,718
Acquisition of radio stations |  |  |  | 0 | 43 |
Acquisition of radio stations - CBS Radio Merger |  |  |  | 0 | 820,961 |
Disposition of Licenses - EMF Sale |  |  |  | 0 | (266) |
Acqusition of radio Stations - Beasley Transaction |  |  |  | 0 | 289 |
Acquisition of radio stations - iHeartMedia Transaction |  |  |  | 0 | 11,700 |
Disposition of radio stations - iHeartMedia Transaction |  |  |  | 0 | (14) |
Assets held for sale |  |  |  | 0 | (2,990) |
Acquisition of radio stations - Emmis Acquisition |  |  |  | 332 | 0 |
Acquisition Of Radio Station - Jerry Lee Acquisition |  |  |  | 24,396 | 0 |
Disposition Of Radio Stations -WXTU Transaction |  |  |  | (8,623) | 0 |
Goodwill, Impairment Loss |  |  |  | 0 | (441) |
Adjustments to Acquired Goodwill |  |  |  | $ (6,651) | $ 0 |

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