Stock Incentive Plans - Summary of Stock Incentive Plans (Details) - USD ($)		1 Months Ended			3 Months Ended		6 Months Ended		12 Months Ended
	May 12, 2015	Jul. 31, 2017	Jun. 30, 2016	Jul. 31, 2015	Jun. 30, 2017	Mar. 31, 2017	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2013	Jan. 01, 2017	Nov. 29, 2016	Nov. 08, 2016	Jan. 01, 2016	Apr. 30, 2014
Shares Available for Grant
Beginning balance (in shares)		450,499				39,988	39,988
Ending balance (in shares)			1,146,943		450,499		450,499	1,146,943	39,988
Stock Options Outstanding
Beginning balance (in shares)		2,440,851				2,571,220	2,571,220
Options exercised (in shares)							0		0
Ending balance (in shares)			1,464,265		2,440,851		2,440,851	1,464,265	2,571,220
RSUs Outstanding
Beginning balance (in shares)		20,789				20,789	20,789
Ending balance (in shares)			20,789		20,789		20,789	20,789	20,789
Weighted Average Stock Option Exercise Price
Beginning balance (in dollars per share)		$ 2.56				$ 2.52	$ 2.52
Ending balance (in dollars per share)					$ 2.56		$ 2.56		$ 2.52
Weighted Average Remaining Contractual Life (Years)
Weighted Average Remaining Contractual Life (Years)							8 years 5 months 9 days		8 years 9 months 7 days
Options vested, exercisable and expected to vest
Options vested and exercisable (in shares)					1,297,589		1,297,589
Options vested and exercisable (in dollars per share)					$ 3.21		$ 3.21
Options vested and exercisable (in years)							7 years 11 months 5 days
Options vested and expected to vest (in shares)					2,128,319		2,128,319
Options vested and expected to vest (in dollars per share)					$ 2.60		$ 2.60
Options vested and expected to vest (in years)							8 years 4 months 17 days
Weighted average grant date fair value of stock options granted (in dollars per share)							$ 0.50	$ 1.04
Number of options vested (in shares)							375,011	242,239
Fair value of options vested on grant date							$ 383,370	$ 283,219
Share Price					0.53		$ 0.53		$ 0.716			$ 0.69	$ 0.91
Common Stock
Options vested, exercisable and expected to vest
Share Price					$ 1.00		$ 1.00
2013 Plan
Stock Incentive Plans
Option shares outstanding					565,377		565,377
Stock Options Outstanding
Options granted (in shares)							0
2013 Plan | Stock options
Stock Incentive Plans
Number of shares reserved for issuance										300,000					847,533
Stock Options Outstanding
Options granted (in shares)										0
2014 Plan
Shares Available for Grant
Additional shares authorized (in shares)							280,142
Stock Options Outstanding
Options granted (in shares)					20,000	18,000
Options cancelled (in shares)					(107,799)	(60,570)
Weighted Average Stock Option Exercise Price
Options granted (in dollars per share)					$ 0.79	$ 0.71
Options cancelled (in dollars per share)					$ 1.47	$ 1.67
2014 Plan | Stock options
Stock Incentive Plans
Number of shares reserved for issuance	333,333
Increase in shares reserve based on outstanding number of shares											280,142			162,498
Increase in share reserve based on outstanding number of shares (as a percent)	2.00%
Shares Available for Grant
Additional shares authorized (in shares)		6,500,188	1,550,000	550,000