Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Accumulated impairment charges		$ 123,100	$ 98,000
Reduction in carrying about of goodwill		1,343	1,328
Impairment charges	$ 25,100	122,227	106,603	$ 4,486
Aggregate amortization expense		42,200	46,200	$ 43,000
impairments of intangibles and property and equipment associated with the sale of a subsidiary		$ 97,100	8,600
Hypothetical decrease (as a percentage)		20.00%
National Networks [Member]
Goodwill [Line Items]
Reduction in carrying about of goodwill		$ 1,343	1,328
International And Other [Member]
Goodwill [Line Items]
Reduction in carrying about of goodwill		$ 0	$ 0

The hypothetical percent decrease applied to evaluate the sensitivity of the fair value calculations.

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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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.

+ References

No definition available.

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- Definition

Amount of (increase) decrease to an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from the subsequent recognition of deferred tax assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 350
-SubTopic 20
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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

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