Credit Facility (Detail)	6 Months Ended
	Jun. 30, 2017 USD ($)
Line of Credit Facility [Line Items]
Revolving credit facility, maximum borrowing capacity	$ 2,500,000
Credit facility expiration date	Jan. 15, 2018
Credit facility limit restricted to support letter of credit	$ 507,381
Line of credit facility, remaining borrowing capacity	$ 2,000,000
Prime Rate
Line of Credit Facility [Line Items]
Interest rate over prime rate	0.50%