Accounts Receivable (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018
Summary of accounts receivable
Total gross receivables	$ 3,796,509	$ 2,586,221	$ 14,723
Less: allowance for doubtful accounts	(839,895)	(839,895)
Total net receivables	2,956,614	1,746,326
Block sales [Member]
Summary of accounts receivable
Total gross receivables
Construction revenue [Member]
Summary of accounts receivable
Total gross receivables	2,826,999	1,619,498
Engineering services [Member]
Summary of accounts receivable
Total gross receivables	416,894	400,877
Retainage receivable [Member]
Summary of accounts receivable
Total gross receivables	544,910	543,417
Other receivable [Member]
Summary of accounts receivable
Total gross receivables	$ 7,706	$ 7,706