Impairment and Related Charges (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Supplemental Income Statement Elements [Abstract]
Impairment and related charges	$ 4,486	$ 28,148	$ 67,805
Gain (Loss) on Sale of Assets and Asset Impairment Charges		(11,000)
Other Asset Impairment Charges	$ 4,486	$ 17,112	67,805
Impairment of Real Estate			22,900
Impairment of Intangible Assets, Finite-lived			17,700
Goodwill, Impairment Loss			$ 27,200

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.

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- Definition

Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

+ References

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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.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

+ References

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The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

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- References

No definition available.

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