Major Customers - Narrative (Details) - Customer Concentration Risk - customer |
12 Months Ended | |
---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
|
Sales Revenue, Services, Net | ||
Concentration Risk [Line Items] | ||
Concentration risk, number of customers | 2 | 2 |
Sales Revenue, Services, Net | Major Customer Number One | ||
Concentration Risk [Line Items] | ||
Concentration risk, percentage | 23.00% | 16.00% |
Sales Revenue, Services, Net | Major Customer Number Two | ||
Concentration Risk [Line Items] | ||
Concentration risk, percentage | 16.00% | 12.00% |
Accounts Receivable | Major Customer Number One | ||
Concentration Risk [Line Items] | ||
Concentration risk, percentage | 65.00% | |
Accounts Receivable | Major Customer Number Two | ||
Concentration Risk [Line Items] | ||
Concentration risk, percentage | 1.00% |