Consolidated Balance Sheets (Parenthetical) - USD ($)	Mar. 31, 2019	Mar. 31, 2018
Allowance for doubtful accounts receivable, net	$ 51,096	$ 82,102
Preferred stock, par value	$ 1.00	$ 1.00
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued
Preferred stock, shares outstanding
Common Class A [Member]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000	100,000
Common stock, shares issued
Common stock, shares outstanding
Common Class B [Member]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	38,464,753	38,282,028
Common stock, shares outstanding	38,464,753	38,282,028