XML 36 R26.htm IDEA: XBRL DOCUMENT v3.19.1
Summary of significant accounting policies (Details) - USD ($)
$ in Thousands
Mar. 31, 2019
Jan. 01, 2019
Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]      
Operating lease right-of-use asset $ 18,678    
Operating lease liability $ 27,152    
Deferred rent     $ 9,100
ASU 2016-02      
New Accounting Pronouncements or Change in Accounting Principle [Line Items]      
Operating lease liability   $ 28,100