Schedule of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Goodwill, Gross	$ 316,858	$ 331,884	$ 0
Goodwill, Impairment Loss	12,628	0
Goodwill, Other Increase (Decrease)	1,159	0
Goodwill, Impaired, Accumulated Impairment Loss	(2,715)	0	0
Goodwill	314,143	331,884	$ 0
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Goodwill [Line Items]
Goodwill, Impairment Loss	0	0
Goodwill, Written off Related to Sale of Business Unit	4,454	0
Goodwill, Gross [Member]
Goodwill [Line Items]
Goodwill, Impairment Loss	0	0
Goodwill, Other Increase (Decrease)	1,159	0
Goodwill, Gross [Member] \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Goodwill [Line Items]
Goodwill, Impairment Loss	9,913	0
Goodwill, Written off Related to Sale of Business Unit	4,454	0
Accumulated Impairment Losses [Member]
Goodwill [Line Items]
Goodwill, Impairment Loss	12,628	0
Goodwill, Other Increase (Decrease)	0	0
Accumulated Impairment Losses [Member] \| Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Goodwill [Line Items]
Goodwill, Impairment Loss	9,913	0
Goodwill, Written off Related to Sale of Business Unit	$ 0	$ 0

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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