v3.26.1
SEGMENT INFORMATION - Segment property, plant and equipment, at cost, less accumulated depreciation (Details) - USD ($)
Mar. 31, 2026
Sep. 30, 2025
Mar. 31, 2025
SEGMENT INFORMATION      
Property and equipment, net $ 54,176,170 $ 53,467,967 $ 52,321,577
Underground Infrastructure Construction      
SEGMENT INFORMATION      
Property and equipment, net 38,467,067   36,867,738
Industrial Construction      
SEGMENT INFORMATION      
Property and equipment, net 14,382,021   14,406,528
Building Construction      
SEGMENT INFORMATION      
Property and equipment, net 1,231,954   1,006,618
Operating Segments      
SEGMENT INFORMATION      
Property and equipment, net 54,081,042   52,280,884
Operating Segments | Underground Infrastructure Construction      
SEGMENT INFORMATION      
Property and equipment, net 38,467,067   36,867,738
Operating Segments | Industrial Construction      
SEGMENT INFORMATION      
Property and equipment, net 14,382,021   14,406,528
Operating Segments | Building Construction      
SEGMENT INFORMATION      
Property and equipment, net 1,231,954   1,006,618
Corporate      
SEGMENT INFORMATION      
Property and equipment, net $ 95,128   $ 40,693