Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)			12 Months Ended
	Sep. 28, 2016	Jul. 05, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Summary Of Significant Accounting Policies [Line Items]
Proceeds from sale of preferred stock			$ 3,000,000
Cash and cash equivalents			930,397	$ 21,547	$ 216,733
Cash and cash equivalents, FDIC insured limit amount			250,000
Unrecognized tax benefits			0	0
Significant increase or decrease within next twelve months			0
Interest or penalties			$ 0	$ 0
Income tax examination, description			Tax years from 2014 to 2016 are generally subject to examination by taxing authorities, (although net operating losses from all years are subject to examinations and adjustments for at least three years following the year in which the attributes are used.)
Preferred stock converted into common stock			5,154,674	3,468,804
Outstanding stock options and warrants			12,116,334	8,054,346
Dilutive securities not included in calculation of loss per common share			0	0
Non-cash impairment loss on investment			$ 0	$ 300,000
Transfers between level 1, 2 or 3				0
Dividend yield assumed			0.00%
Dividend expected to be paid			$ 0
Source One [Member]
Summary Of Significant Accounting Policies [Line Items]
Impairment of investment				$ 200,000
Earliest Tax Year [Member]
Summary Of Significant Accounting Policies [Line Items]
Tax years, subject to examination by taxing authorities			2014
Latest Tax Year [Member]
Summary Of Significant Accounting Policies [Line Items]
Tax years, subject to examination by taxing authorities			2016
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of assets			3 years
Income tax examination period			3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of assets			5 years
Credit Concentration Risk [Member]
Summary Of Significant Accounting Policies [Line Items]
Cash and cash equivalents			$ 0
Angionetics Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
Non-controlling interest, voting interest percentage	15.00%	5.60%
Series A Convertible Preferred Stock [Member]
Summary Of Significant Accounting Policies [Line Items]
Series A Convertible Preferred stock, shares issued			928	1,041
Outstanding convertible preferred stock			928	1,041
Series A Convertible Preferred Stock [Member] | Angionetics Inc. [Member]
Summary Of Significant Accounting Policies [Line Items]
Series A Convertible Preferred stock, shares issued	400,000	200,000
Proceeds from sale of preferred stock	$ 2,000,000	$ 1,000,000