Annual report pursuant to Section 13 and 15(d)

License Agreements (Details)

License Agreements (Details)							3 Months Ended				12 Months Ended
License Agreements (Details)	Apr. 01, 2017 USD ($) salesperson	Sep. 22, 2016 USD ($)	Dec. 18, 2015 USD ($) unit	Dec. 01, 2014 kg	May 31, 2011	May 19, 2008 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2014 USD ($)
Asset Acquisition And License Agreement [Line Items]
Sales force revenue							$ 278,000	$ 0	$ 0	$ 0	$ 278,165	$ 0	$ 0
Merck \| CERC-301
Asset Acquisition And License Agreement [Line Items]
Other commitment															$ 750,000
Merck \| CERC-301 \| Research and development
Asset Acquisition And License Agreement [Line Items]
Asset acquisition payments														$ 750,000
Merck \| COMT Inhibitor
Asset Acquisition And License Agreement [Line Items]
Asset acquisition payments														$ 200,000
Lilly \| License Agreement To Develop Transmembrane Ampa Receptor Regulatory Proteins
Asset Acquisition And License Agreement [Line Items]
Asset acquisition payments		$ 2,000,000
Potential milestone commitment due within 30 days		$ 750,000
Time period within execution of license agreement		30 days
Potential milestone commitment due after first subject closed		$ 1,250,000
TRx \| Merck \| Metafolin Supply Agreement
Asset Acquisition And License Agreement [Line Items]
Percentage Metafolin requirements contracted to purchase				100.00%
Product royalty				2.00%
Purchase commitment minimum mass required \| kg				1
Royalty payment period				45 days
TRx \| Mead Johnson and Company LLC \| Poly-Vi-Flor And Tri-Vi-Flor License
Asset Acquisition And License Agreement [Line Items]
Product royalty				10.00%
Royalty payment period				45 days
TRx \| Presmar Associates \| Poly-Vi-Flor Trademark
Asset Acquisition And License Agreement [Line Items]
Product royalty					5.00%
Royalty payment period					45 days
TRx \| PAI \| PAI Sales & Marketing Agreement
Asset Acquisition And License Agreement [Line Items]
Number of salespersons \| salesperson	16
Monthly payment	$ 62,500
Product sales revenue share	50.00%
Duration of revenue sharing beyond contract termination	6 months
Contract term	6 months
Automatic renewal period	6 months
Contract cancellation notice period	90 days
Sales force revenue											$ 90,000
TRx \| Watson Laboratories \| License And Supply Agreement For Millipred Tablets
Asset Acquisition And License Agreement [Line Items]
Contract term						5 years
Automatic renewal period						1 year
Semi-annual license payment						$ 75,000
Zylera \| Lachlan Pharmaceuticals \| Ulesfia Supply Agreement
Asset Acquisition And License Agreement [Line Items]
Minimum royalty			$ 3,000,000
Minimum revenue basis for royalty payment			20,000,000
Potential milestone revenue threshold number one			90,000,000
Potential milestone revenue threshold number two			180,000,000
Potential milestone revenue threshold number three			270,000,000
Potential milestone revenue threshold number four			400,000,000
Potential milestone payment number one			3,000,000
Potential milestone payment number two			3,500,000
Potential milestone payment number three			4,000,000
Potential milestone payment number four			$ 5,000,000
Minimum quantity required \| unit			20,000
Long-term purchase commitment			$ 1,117,700
Consecutive periods within twelve months orders unfilled			6 months
Periods within twelve months orders unfilled			9 months
Purchase commitment measurement period			12 months
Minimum \| TRx \| Merck \| Metafolin Supply Agreement
Asset Acquisition And License Agreement [Line Items]
Product target age				0 years
Maximum \| TRx \| Merck \| Metafolin Supply Agreement
Asset Acquisition And License Agreement [Line Items]
Product target age				3 years
Tier One \| Zylera \| Lachlan Pharmaceuticals \| Ulesfia Supply Agreement
Asset Acquisition And License Agreement [Line Items]
Product royalty			15.00%
Tier One \| Maximum \| Zylera \| Lachlan Pharmaceuticals \| Ulesfia Supply Agreement
Asset Acquisition And License Agreement [Line Items]
Royalty revenue threshold			$ 50,000,000
Tier Two \| Zylera \| Lachlan Pharmaceuticals \| Ulesfia Supply Agreement
Asset Acquisition And License Agreement [Line Items]
Product royalty			20.00%
Tier Two \| Minimum \| Zylera \| Lachlan Pharmaceuticals \| Ulesfia Supply Agreement
Asset Acquisition And License Agreement [Line Items]
Royalty revenue threshold			$ 50,000,000
Tier Three \| Zylera \| Lachlan Pharmaceuticals \| Ulesfia Supply Agreement
Asset Acquisition And License Agreement [Line Items]
Product royalty			25.00%
Tier Three \| Minimum \| Zylera \| Lachlan Pharmaceuticals \| Ulesfia Supply Agreement
Asset Acquisition And License Agreement [Line Items]
Royalty revenue threshold			$ 100,000,000