Condensed Consolidated Statements of Stockholders' Equity (Parenthetical) (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2019	Sep. 30, 2018	Mar. 31, 2018
Statement Of Stockholders Equity [Abstract]
Stock issuance costs and discounts	$ 54	$ 907	$ 4,611