Statements of Convertible Preferred Stock and Stockholders’ Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Series G
Temporary equity, adjustment upon conversion		$ 1,123
Temporary equity, issuance costs	$ 27	267
Series F
Temporary equity, issuance costs		$ 21
Series H
Temporary equity, issuance costs	$ 284