Debt - Revolving Borrowings (Details) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Summary of company's revolving borrowings | ||
| Total revolving loans (current) | $ 52,844 | $ 23,149 |
| Maximum remaining available to be borrowed under revolving lines of credit | $ 100,237 | $ 23,067 |