Consolidated Statements of Operations (Unaudited) - USD ($)
 3 Months Ended 9 Months Ended
May 31, 2022
May 31, 2021
May 31, 2022
May 31, 2021
NET SALES:        
Net sales, excluding joint ventures $ 18,436,253 $ 14,164,604 $ 51,654,355 $ 38,619,353
Net sales, to joint ventures 528,668 1,253,920 2,252,618 2,361,165
Total net sales 18,964,921 15,418,524 53,906,973 40,980,518
Cost of goods sold 12,722,833 10,152,582 36,977,620 [1] 26,997,582 [1]
Gross profit 6,242,088 5,265,942 16,929,353 13,982,936
JOINT VENTURE OPERATIONS:        
Equity in income from joint ventures 1,364,597 2,033,536 3,662,178 5,779,260
Fees for services provided to joint ventures 1,329,988 1,589,621 3,835,755 4,388,866
Total joint venture operations 2,694,585 3,623,157 7,497,933 10,168,126
OPERATING EXPENSES:        
Selling expenses 3,450,308 3,171,657 9,659,457 8,745,433
General and administrative expenses 2,560,487 2,072,195 7,675,622 6,125,151
Research and development expenses 1,102,942 1,066,493 3,557,437 3,217,410
Total operating expenses 7,113,737 6,310,345 20,892,516 18,087,994
OPERATING INCOME 1,822,936 2,578,754 3,534,770 6,063,068
REMEASUREMENT GAIN ON ACQUISITION OF EQUITY METHOD INVESTEE 0 0 3,951,550 0
INTEREST INCOME 15,925 10,676 36,777 95,852
INTEREST EXPENSE (23,784) (3,044) (34,079) (10,661)
INCOME BEFORE INCOME TAX EXPENSE 1,815,077 2,586,386 7,489,018 6,148,259
INCOME TAX EXPENSE 604,314 276,338 1,260,437 929,588
NET INCOME 1,210,763 2,310,048 6,228,581 5,218,671
NET INCOME ATTRIBUTABLE TO NON-CONTROLLING INTERESTS 210,596 256,132 551,808 589,781
NET INCOME ATTRIBUTABLE TO NTIC $ 1,000,167 $ 2,053,916 $ 5,676,773 $ 4,628,890
NET INCOME ATTRIBUTABLE TO NTIC PER COMMON SHARE:        
Basic (in dollars per share) $ 0.11 $ 0.23 $ 0.62 $ 0.51
Diluted (in dollars per share) $ 0.11 $ 0.21 $ 0.59 $ 0.47
WEIGHTED AVERAGE COMMON SHARES ASSUMED OUTSTANDING:        
Basic (in shares) 9,227,912 9,109,861 9,216,216 9,107,243
Diluted (in shares) 9,578,797 9,972,000 9,682,646 9,829,052
CASH DIVIDENDS DECLARED PER COMMON SHARE (in dollars per share) $ 0.07 $ 0.065 $ 0.21 $ 0.13
[1] The percent of segment sales is calculated by dividing the direct cost of goods sold for each individual segment category by the net sales for each segment category.