Business Segment, Geographic and Major Customer Information (Major Customers) (Details) - Customer Concentration Risk - Sales Revenue, Net	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Major Customers [Member] \| Energy Chemistry Technologies
Revenue, Major Customer [Line Items]
Concentration risk, percentage	95.00%	95.00%	95.00%
Customer A
Revenue, Major Customer [Line Items]
Concentration risk, percentage	12.80%	15.70%	17.20%
Customer B
Revenue, Major Customer [Line Items]
Concentration risk, percentage	8.90%	13.20%	14.60%
Customer C
Revenue, Major Customer [Line Items]
Concentration risk, percentage	4.00%	6.90%	10.60%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration