Warrants - Additional Information (Detail)				1 Months Ended				6 Months Ended	12 Months Ended
	Sep. 07, 2018 shares	Jul. 11, 2018 USD ($) shares	Jun. 29, 2018 USD ($) $ / shares shares	Mar. 31, 2018 USD ($)	Aug. 31, 2017 shares	May 31, 2017 shares	Mar. 31, 2017 shares	Jun. 29, 2018 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 $ / shares shares	Sep. 13, 2018 $ / shares	Jun. 30, 2018 USD ($)	Mar. 09, 2017 $ / shares shares	Dec. 31, 2016 shares
Class Of Warrant Or Right [Line Items]
Stock issued for exchange of warrants, shares													1,659
Cashless exercises of warrants							22,063
Replacement warrants issued in connection with the Mergers						155				155
Issuances					78,181				7,342,530	79,840
Conversion of warrants into common stock and cash									76,569
Warants outstanding									7,344,297	78,336				20,404
Stock price per share | $ / shares									$ 0.0001	$ 0.0001	$ 0.0001
Cash proceeds from common stock | $									$ 4,334,816
Gain on exchange of warrants | $									779,923
Exchange consideration discounted percentage								0.05
Warrants right grant date fair value | $									$ 23,511,785
Warrants exercise price per share | $ / shares									$ 5.03				$ 0.01
Series B Preferred Stock [Member]
Class Of Warrant Or Right [Line Items]
Face value of preferred stock | $												$ 2,364,044
First Exchange Warrants [Member]
Class Of Warrant Or Right [Line Items]
Stock issued for exchange of warrants, shares			53,125					53,125	73,530
Issuance of common stock for the exchange of warrants			167,700
Stock price per share | $ / shares			$ 12.60					$ 12.60
Convertible notes principal balance | $			$ 1,500,000					$ 1,500,000	$ 1,500,000
Cash proceeds from common stock | $			$ 1,100,000
Proceeds from exchange of warrants | $									4,727,000
Converted value in excess of principal | $				$ 3,467,935
Gain on exchange of warrants | $									(3,593,082)
Transaction costs | $									125,147
First Exchange Warrants [Member] | Series B Preferred Stock [Member]
Class Of Warrant Or Right [Line Items]
Face value of preferred stock | $									$ 2,364,044
Second Warrants Exchange [Member]
Class Of Warrant Or Right [Line Items]
Stock issued for exchange of warrants, shares		22,523
Stock price per share | $ / shares									$ 8.64
Number of shares issued		32,124
Additional number of shares issued		145,038
Second Warrants Exchange [Member] | Series B Preferred Stock [Member]
Class Of Warrant Or Right [Line Items]
Number of shares issued		32,124
Proceeds from issuance of warrants | $		$ 22,241
Third Warrants Exchange [Member]
Class Of Warrant Or Right [Line Items]
Stock issued for exchange of warrants, shares	921
Stock price per share | $ / shares									$ 8.85
Number of shares issued	5,929
Warrants Issued with Redeemable Preferred [Member]
Class Of Warrant Or Right [Line Items]
Warants outstanding									1,612	78,181
Warrants exercise price per share | $ / shares									$ 80.10	$ 80.10
Maximum [Member]
Class Of Warrant Or Right [Line Items]
Stock issued for exchange of warrants, shares							1,659
Merger Agreement [Member}
Class Of Warrant Or Right [Line Items]
Number of warrants exercised							22,022