Subsequent events (Details)				1 Months Ended		2 Months Ended	6 Months Ended	12 Months Ended
	Jul. 10, 2015	Jul. 09, 2015 $ / shares shares	Jun. 30, 2015 USD ($) $ / shares shares	Jul. 27, 2015 USD ($) $ / shares shares	Jul. 27, 2015 USD ($) $ / shares shares	Aug. 27, 2015 $ / shares shares	Jun. 30, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) shares	Jul. 28, 2015 shares	Nov. 30, 2009 shares
Subsequent events disclosures
Common stock, authorized shares			35,000,000				35,000,000	35,000,000
Neos Therapeutics, Inc. 2009 Equity Plan
Subsequent events disclosures
Shares reserved for issuance under the plan			1,375,037				1,375,037			688,059
Common stock warrants issued with Series B-1 redeemable preferred stock financing
Subsequent events disclosures
Proceeds from exercise of warrants (in dollars) | $							$ 0	$ 0
Series C preferred stock | Series C Warrants Issued with Series C Redeemable Preferred Stock Financing
Subsequent events disclosures
Number of shares issued upon exercise of warrants			150,000	1,000,000
Exercise price of warrants (in dollars per share) | $ / shares			$ 5.00	$ 5.00	$ 5.00		$ 5.00
Proceeds from exercise of warrants (in dollars) | $			$ 750,000	$ 5,000,000
Subsequent event
Subsequent events disclosures
Common stock, authorized shares									100,000,000
Preferred stock, authorized shares									5,000,000
Subsequent event | Neos Therapeutics, Inc. 2015 Stock Option and Incentive Plan
Subsequent events disclosures
Shares reserved for issuance under the plan				767,330	767,330
Subsequent event | Non-employee stock option | Neos Therapeutics, Inc. 2015 Stock Option and Incentive Plan | Director | Effective Upon Completion of Initial Public Offering
Subsequent events disclosures
Grants (in shares)		37,500
Exercise price (in dollars per share) | $ / shares		$ 15.00
Subsequent event | Common Stock
Subsequent events disclosures
Reverse stock split ratio	0.4167
Subsequent event | Common stock warrants issued with Series B-1 redeemable preferred stock financing | Common Stock
Subsequent events disclosures
Number of shares issued upon exercise of warrants						99,062
Exercise price of warrants (in dollars per share) | $ / shares						$ 0.0024
Subsequent event | Series C preferred stock | Series C Warrants Issued with Series C Redeemable Preferred Stock Financing
Subsequent events disclosures
Number of shares issued upon exercise of warrants					850,000
Exercise price of warrants (in dollars per share) | $ / shares				$ 5.00	$ 5.00
Proceeds from exercise of warrants (in dollars) | $					$ 4,250,000