CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 678,886	$ 596,602
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, authorized	10,000,000	10,000,000
Preferred stock, issued	0	0
Preferred stock, outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized	350,000,000	350,000,000
Common stock, issued	241,221,840	240,462,439
Common stock, outstanding	241,221,840	240,462,439