Components of Income Tax Provision (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Current tax provision
Federal	$ 0	$ 0
State	0	0
Foreign	33,055,811	4,488,815
Current Income Tax Expense (Benefit), Total	33,055,811	4,488,815
Deferred tax provision (benefit)
Federal	0	0
State	0	0
Foreign	(428,101)	1,849,910
Deferred Income Tax Expense (Benefit), Total	(428,101)	1,849,910
Income tax provision	$ 32,627,710	$ 6,338,725