Leases - Reconciliation of Undiscounted Lease Liabilities to Total Lease Liabilities (Detail) - USD ($)	Jun. 30, 2019	Jan. 01, 2019
Undiscounted lease liabilities for years ending December 31,:
2019 (remaining)	$ 112,615
2020	229,323
2021	186,784
2022	72,400
Total undiscounted lease liabilities	601,122
Less effects of discounting	(63,157)
Total lease liabilities	537,965	$ 400,000
Operating lease liability, current	226,421
Operating lease liability, non-current	311,544
Total lease liabilities	$ 537,965	$ 400,000