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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Goodwill - Additional Disclosures (Details)	3 Months Ended		6 Months Ended
Goodwill - Additional Disclosures (Details)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) reporting_unit	Jun. 30, 2017 USD ($)
Goodwill [Line Items]
Number of reporting units \| reporting_unit			2
Goodwill impairment recognized	$ 37,180,000	$ 0	$ 37,180,000	$ 0
Energy Chemical Technologies
Goodwill [Line Items]
Goodwill impairment recognized	37,200,000		37,180,000
Non Energy Chemicals [Member]
Goodwill [Line Items]
Goodwill impairment recognized	$ 0		$ 0