Net Loss Per Share (Details) - USD ($)	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net loss attributable to Inovio Pharmaceuticals, Inc.	$ (23,085,907)	$ (8,042,820)
Reflect adjustment for decrease in fair value of warrant liability	(116,477)	0
Numerator for use in diluted loss per share	$ (23,202,384)	$ (8,042,820)
Weighted average number of common shares outstanding (shares)	74,152,609	72,230,411
Effect of dilutive potential common shares (shares)	148,275	0
Denominator for use in diluted loss per share (shares)	74,300,884	72,230,411
Net loss per share, diluted ($ per share)	$ (0.31)	$ (0.11)
Antidilutive securities excluded (shares)	9,227,018	8,437,652
Options to purchase commons stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded (shares)	7,841,669	7,135,624
Warrants to purchase common stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded (shares)	0	560,904
Restricted stock units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded (shares)	1,376,893	732,668
Convertible preferred stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded (shares)	8,456	8,456

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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