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Basis of Presentation and Significant Accounting Policies - Additional Information (Details) - Customer Concentration Risk [Member] - Customer | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015 | Dec. 31, 2015
Revenues [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Number of major customers | 3 | 2 | 4 | 2 |
Revenues [Member] | Customer 1 [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk, percentage (in hundredths) | 51.00% | 57.00% | 30.00% | 59.00% |
Revenues [Member] | Customer 2 [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk, percentage (in hundredths) | 37.00% | 20.00% | 21.00% | 22.00% |
Revenues [Member] | Customer 3 [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk, percentage (in hundredths) | 12.00% |  | 18.00% |  |
Revenues [Member] | Customer 4 [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk, percentage (in hundredths) |  |  | 10.00% |  |
Trade And Other Receivables [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Number of major customers |  |  | 2 |  | 4
Trade And Other Receivables [Member] | Customer 1 [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk, percentage (in hundredths) |  |  | 68.00% |  | 39.00%
Trade And Other Receivables [Member] | Customer 2 [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk, percentage (in hundredths) |  |  | 20.00% |  | 25.00%
Trade And Other Receivables [Member] | Customer 3 [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk, percentage (in hundredths) |  |  |  |  | 18.00%
Trade And Other Receivables [Member] | Customer 4 [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk, percentage (in hundredths) |  |  |  |  | 10.00%

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- Definition 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. + References 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=64851502&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=73719730&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=64851502&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=73719730&loc=d3e13537-108611 + Details
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