Stock Options and Warrants - Summary of Outstanding Warrants Related to Warrant Transactions (Detail) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Class of Warrant or Right [Line Items]
Number of Shares, Outstanding, Beginning balance	126,206	850,058
Warrants, Issued	11,159,995
Warrants, Exercised	(641,257)	(517,035)
Warrants, Forfeited/Cancelled	(3,037,762)	(206,815)
Warrants, Rounding due to July 29, 2015 reverse stock split		(2)
Number of Shares, Outstanding, Ending balance	7,607,182	126,206
Weighted Average
Class of Warrant or Right [Line Items]
Weighted Average Exercise Price, Outstanding, Beginning balance	$ 15.82	$ 10.31
Weighted Average Exercise Price, Issued	2.42
Weighted Average Exercise Price, Exercised	1.75	2.40
Weighted Average Exercise Price, Forfeited/Cancelled	1.86	11.25
Weighted Average Exercise Price, Outstanding, Ending balance	2.43	15.82
Minimum [Member]
Class of Warrant or Right [Line Items]
Weighted Average Exercise Price, Outstanding, Beginning balance	1.79	8.64
Weighted Average Exercise Price, Issued	1.75
Weighted Average Exercise Price, Exercised	1.75	1.79
Weighted Average Exercise Price, Forfeited/Cancelled	1.75	11.25
Weighted Average Exercise Price, Outstanding, Ending balance	1.75	1.79
Maximum [Member]
Class of Warrant or Right [Line Items]
Weighted Average Exercise Price, Outstanding, Beginning balance	300.00	300.00
Weighted Average Exercise Price, Issued	3.64
Weighted Average Exercise Price, Exercised		6.72
Weighted Average Exercise Price, Forfeited/Cancelled	300.00
Weighted Average Exercise Price, Outstanding, Ending balance	$ 30.00	$ 300.00
January Two Thousand Thirteen Financing
Class of Warrant or Right [Line Items]
Number of Shares, Outstanding, Beginning balance	33,750	33,750
Number of Shares, Outstanding, Ending balance	33,750	33,750
March Two Thousand Thirteen Financing
Class of Warrant or Right [Line Items]
Number of Shares, Outstanding, Beginning balance	16,667	16,667
Number of Shares, Outstanding, Ending balance	16,667	16,667
March 2016 Financing [Member] | Series A Common Stock [Member]
Class of Warrant or Right [Line Items]
Warrants, Issued	3,605,713
Number of Shares, Outstanding, Ending balance	3,605,713
March 2016 Financing [Member] | Series B Common Stock [Member]
Class of Warrant or Right [Line Items]
Warrants, Issued	3,605,713
Warrants, Exercised	(569,285)
Warrants, Forfeited/Cancelled	(3,036,428)
March 2016 Financing [Member] | Series C Common Stock [Member]
Class of Warrant or Right [Line Items]
Warrants, Issued	3,605,713
Number of Shares, Outstanding, Ending balance	3,605,713
March 2016 Financing [Member] | Placement Agent [Member]
Class of Warrant or Right [Line Items]
Warrants, Issued	342,856
Number of Shares, Outstanding, Ending balance	342,856
October 2014 Financing [Member] | Series A Common Stock [Member]
Class of Warrant or Right [Line Items]
Number of Shares, Outstanding, Beginning balance	12,408	258,519
Warrants, Exercised	(12,408)	(246,108)
Warrants, Rounding due to July 29, 2015 reverse stock split		(3)
Number of Shares, Outstanding, Ending balance		12,408
October 2014 Financing [Member] | Series B Common Stock [Member]
Class of Warrant or Right [Line Items]
Number of Shares, Outstanding, Beginning balance		219,224
Warrants, Exercised		(12,409)
Warrants, Forfeited/Cancelled		(206,815)
October 2014 Financing [Member] | Series C Common Stock [Member]
Class of Warrant or Right [Line Items]
Number of Shares, Outstanding, Beginning balance		258,519
Warrants, Exercised		(258,518)
Warrants, Rounding due to July 29, 2015 reverse stock split		(1)
October 2014 Financing [Member] | Placement Agent [Member]
Class of Warrant or Right [Line Items]
Number of Shares, Outstanding, Beginning balance	62,047	62,045
Warrants, Exercised	(59,564)
Warrants, Rounding due to July 29, 2015 reverse stock split		2
Number of Shares, Outstanding, Ending balance	2,483	62,047
Skin Care [Member]
Class of Warrant or Right [Line Items]
Number of Shares, Outstanding, Beginning balance	1,334	1,334
Warrants, Forfeited/Cancelled	(1,334)
Number of Shares, Outstanding, Ending balance	0	1,334