Stockholders’ and Mezzanine equity - Mezzanine Equity - Tabular Disclosure (Details)
$ in Thousands
12 Months Ended
Dec. 31, 2016
USD ($)
Stockholders’ and Mezzanine equity  
Series A preferred stock, at issuance (net) $ 87,922
Dividends on preferred stock 940
Accretion on preferred stock 113
Mezzanine equity at end of period $ 88,975