Loan Arrangement with Former Related Party - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Feb. 29, 2016	Sep. 30, 2019	Oct. 22, 2019	Jun. 30, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Common stock, shares outstanding		206,407,551			187,029,967
Remaining debt amount		$ 70,019			$ 72,089
Promissory notes		70,019			$ 72,089
The Mann Group LLC
Related Party Transaction [Line Items]
Remaining debt amount				$ 72,000
Accrued interest due to related party				$ 9,100
Promissory notes		$ 70,000
The Mann Group LLC | Loan Arrangement
Related Party Transaction [Line Items]
Trustee substantial portion disposed term	3 years
Additional common stock shares reserved for issuance		14,000,000
The Mann Group LLC | Loan Arrangement | Subsequent Event
Related Party Transaction [Line Items]
Common stock, shares outstanding			9,200,000
The Mann Group LLC | Loan Arrangement | Common Stock
Related Party Transaction [Line Items]
Written notice period		65 days
The Mann Group LLC | Loan Arrangement | Maximum | Subsequent Event
Related Party Transaction [Line Items]
Percentage of common stock shares outstanding			5.00%
The Mann Group LLC | Loan Arrangement | Maximum | Common Stock
Related Party Transaction [Line Items]
Percentage of beneficially own in excess		19.99%
The Mann Group LLC | Loan Arrangement | Minimum | Common Stock
Related Party Transaction [Line Items]
Percentage of beneficially own in excess		9.99%
Mr.Mann | Loan Arrangement | Common Stock
Related Party Transaction [Line Items]
Percentage of beneficial interest owned	36.00%