Income Taxes - Schedule of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance of unrecognized tax benefits	$ 2,030	$ 1,248	$ 1,132
Gross increases based on tax positions related to current year	0	633	116
Gross decreases based on tax positions related to prior years	(634)	0	0
Gross increases based on tax positions related to prior year	91	149	0
Settlements with taxing authorities	0	0	0
Expiration of statue of limitations	0	0	0
Ending balance of unrecognized tax benefits	$ 1,487	$ 2,030	$ 1,248