Acquisition and Divestiture-Related Activities Divestiture (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Divestiture-Related Activities [Abstract]
(Losses) gains on divestitures, net	$ (9,643)	$ 6,865	$ (9,097)	$ 8,141
Impairment losses	(2,180)	0	(4,604)	(794)
(Losses) gains on divestitures and impairment charges, net	$ (11,823)	$ 6,865	$ (13,701)	$ 7,347

Amount, before tax, of (gain) loss recognized for the (reversal of write-down) write-down to fair value, less cost to sell, of a disposal group. Excludes discontinued operations.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration