Amount of fresh-start adjustment to goodwill.

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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.

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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.

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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.

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Intangible Assets and Goodwill (Changes in Goodwill) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 04, 2018	Jun. 03, 2018	Dec. 31, 2017
Goodwill [Line Items]
Impact of fresh start accounting		$ (135,214)
Radio Station Group
Goodwill [Line Items]
Impact of fresh start accounting		0
Westwood One
Goodwill [Line Items]
Impact of fresh start accounting		(135,214)
Predecessor Company
Goodwill [Line Items]
Goodwill			$ 1,582,806	$ 1,582,806
Accumulated impairment losses			(1,447,592)	(1,447,592)
Total			135,214	135,214
Predecessor Company \| Radio Station Group
Goodwill [Line Items]
Goodwill			1,278,526	1,278,526
Accumulated impairment losses			(1,278,526)	(1,278,526)
Total			0	0
Predecessor Company \| Westwood One
Goodwill [Line Items]
Goodwill			304,280	304,280
Accumulated impairment losses			(169,066)	(169,066)
Total			$ 135,214	$ 135,214
Successor Company
Goodwill [Line Items]
Total	$ 0	0
Successor Company \| Radio Station Group
Goodwill [Line Items]
Total		0
Successor Company \| Westwood One
Goodwill [Line Items]
Total		$ 0