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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Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Intangible Assets and Goodwill - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Mar. 31, 2018	Jun. 30, 2018	Dec. 31, 2018
Goodwill
Goodwill asset impaired		$ 90,976
Glemba
Goodwill
Amount of carrying amount in excess of fair value amount			$ 91,000
Goodwill asset impaired	$ 91,000