Business Combination (Schedule of Components of Purchase Price and Net Assets Acquired) (Details) - Curetis N.V [Member]	9 Months Ended
	Sep. 30, 2021 USD ($) $ / shares shares
Purchase Price
Number of shares issued to Curetis N.V | shares	2,028,208
Multiplied by the market value per share of OpGen's common stock | $ / shares	$ 2.39	[1]
Total fair value of common stock issued to Curetis N.V shareholders	$ 4,847,417
Fair value of replacement stock awards related to precombination service	136,912	[2]
Fair value of convertible notes assumed	1,323,750	[3]
Fair value of EIB debt assumed	15,784,892	[4]
Funds advanced to Curetis GmbH under Interim Facility	4,808,712
Cash and cash equivalents and restricted cash acquired	(1,266,849)
Purchase Price	$ 25,634,834

[1] The price per share of OpGen’s common stock was based on the closing price as reported on the Nasdaq Capital Market on April 1, 2020.

[2] The fair value of the stock options assumed was determined using the Black-Scholes option pricing model.

[3] To derive the fair value of the convertible notes, the Company estimated the fair value of the convertible notes with and without the derivative liability using a scenario analysis and Monte Carlo simulation.

[4] The fair value of the EIB debt is determined using a discounted cash flow analysis with current applicable rates for similar instruments.