XML 49 R38.htm IDEA: XBRL DOCUMENT v3.19.2
Revenue - Trade Sale Revenue (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Revenue from Contract with Customer [Abstract]          
Trade sales receivable $ 1,972,177   $ 1,972,177   $ 1,606,283
Trade sales payable 1,250,425   1,250,425   $ 1,250,454
Trade sales revenue $ 2,259,366 $ 1,736,658 $ 4,508,242 $ 3,619,088