Note 9 - Net Income Per Common Share - Reconciliation of the Earnings Per Share Computations (Details) - USD ($)	12 Months Ended
	Aug. 31, 2019	Aug. 31, 2018
Net income attributable to NTIC	$ 5,209,622	$ 6,701,366
Basic-weighted shares outstanding (in shares)	9,085,584	9,077,676
Weighted shares assumed upon exercise of stock options (in shares)	330,390	292,728
Diluted – weighted shares outstanding (in shares)	9,415,974	9,370,404
Basic earnings per share: (in dollars per share)	$ 0.57	$ 0.74
Diluted earnings per share: (in dollars per share)	$ 0.55	$ 0.72