Accounts payable and accrued expenses (Tables)

12 Months Ended

Dec. 31, 2017

Accounts payable and accrued expenses [Abstract]

Accounts payable and accrued expenses

Accounts payable and accrued expenses at December 31, 2017 and 2016 are shown as follows:

	2017		2016
General expenses	$	143,409	$	121,589
Purchased services		91,122		67,374
Operating expenses		42,035		160,413
Salaries and wages		1,678		3,893
Taxes payable		1,492		11,032
Other		62,182		41,204
	$	341,918	$	405,505