XML 16 R7.htm IDEA: XBRL DOCUMENT v3.19.2
Consolidated Statements of Stockholders' Equity (Deficit) (Parenthetical)
May 02, 2018
Nov. 06, 2017
Jun. 30, 2019
$ / shares
Dec. 31, 2018
$ / shares
Dec. 31, 2017
$ / shares
Statement Of Stockholders Equity [Abstract]          
Common stock issued, par value     $ 0.01 $ 0.01 $ 0.01
Preferred stock issued, par value     $ 0.01 $ 0.01 $ 0.01
Reverse stock split ratio 0.002 0.0029