Related party transactions (Details Textual) - USD ($)	3 Months Ended		5 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Oct. 31, 2016
Merck Sharp & Dohme Corp [Member]
Related Party Transaction [Line Items]
Research and development agreement description	Under the agreement, Merck will provide access to its archive of over 200,000 bacterial pathogens. OpGen will initially perform molecular analyses on up to 10,000 pathogens to identify markers of resistance to support rapid decision making using the Acuitas Lighthouse, and to speed development of OpGen’s rapid diagnostic products. Merck will gain access to the high-resolution genotype data for the isolates as well as access to OpGen’s Acuitas Lighthouse informatics to support internal research and development programs.
Maximum required amount to expend for procurement of materials				$ 175,000
Merck Sharp & Dohme Corp [Member] | Research and Development Expense [Member]
Related Party Transaction [Line Items]
Procurement costs recognized	$ 59,133		$ 91,403
Fluidigm Corporation Supply Agreement [Member]
Related Party Transaction [Line Items]
Contractual agreement period	5 years
Additional contractual agreement period	5 years
Contractual agreement maturity date	Mar. 17, 2018
Contractual agreement description	The initial term of the Fluidigm Agreement is five years. Both parties have the ability to extend the term for an additional five years. Under the expanded Supply Agreement, the term was extended until March 17, 2018, and the Company has the right to extend the term of the Supply Agreement for up to two additional three-year terms.
Related party transaction, expenses from transactions with related party	$ 44,721	$ 93,224
Related party transaction, purchases from related party	44,721	67,775
Payments to acquire equipment on lease	$ 30,254	$ 45,106