Restatement of Previously Issued Financial Statements - Schedule of Consolidated Statements of Shareholders' Equity, Including Balances Originally Reported, Corrections and Restated Balances (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Accumulated Deficit	$ (113,836)	$ (70,351)	$ 28,349
Total Stockholders' Equity	203,690	159,561	180,497
As Reported
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Accumulated Deficit	(102,180)	(63,517)	30,818
Total Stockholders' Equity	215,346	166,395	182,966
Correction
Error Corrections And Prior Period Adjustments Restatement [Line Items]
Accumulated Deficit	(11,656)	(6,834)	(2,469)
Total Stockholders' Equity	$ (11,656)	$ (6,834)	$ (2,469)