Trade Accounts and Bills Receivable, Net (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Trade Accounts and Bills Receivable, net (Textual)
Trade accounts and bills receivables and retention receivables	$ 1,147,340	$ 1,119,490
Retention receivables interest-free and recoverable period	three to five years