v3.6.0.2

Summary of Significant Accounting Policies - Concentration (Details) - customer | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Sales | Customer |  |  |
Risk and Uncertainties |  |  |
Number of customers exceeding 10% of benchmark | 0 | 0 | 0
Accounts Receivable | Customer |  |  |
Risk and Uncertainties |  |  |
Number of customers exceeding 10% of benchmark | 1 |  |
Concentration risk (as a percent) | 52.00% |  |
Accounts Receivable | Credit |  |  |
Risk and Uncertainties |  |  |
Number of customers exceeding 10% of benchmark |  | 0 |

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