Stock Plans - Additional Information (Detail)	1 Months Ended					12 Months Ended
	Oct. 31, 2017 USD ($)	Sep. 30, 2017 USD ($) Employee	Jan. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) Milestone $ / shares shares	Aug. 31, 2015 USD ($)	Dec. 31, 2017 USD ($) Plan $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Jan. 01, 2018 shares
Stockholders Equity [Line Items]
Number of equity compensation plans | Plan						3
Stock-based compensation expense						$ 4,036,000	$ 2,909,000
Common stock surrendered by employees for payment | shares						3,270
Payments related to withholding taxes due						$ 16,000
Net issuance of shares excluding common stock surrendered by employees for payment | shares						53,136
Shares vested but remained unsettled | shares						29,375
Gross proceeds from issuance of common stock					$ 73,965,000
Common stock withheld pursuant to employee stock purchase plan						$ 35,000	155,000
Research and Development [Member]
Stockholders Equity [Line Items]
Stock-based compensation expense						1,287,000	1,362,000
General and Administrative [Member]
Stockholders Equity [Line Items]
Stock-based compensation expense						$ 2,749,000	$ 1,547,000
Accelerated Vesting of Unvested Restricted Stock Units and Stock Options [Member]
Stockholders Equity [Line Items]
Separation of employee | Employee		10
Charge to operations		$ 158,000
Share based compensation payment award, plan modification, description and terms						Inotek also modified the employment agreements with certain of its remaining employees such that in the event of a change in control, if the employee experiences a qualifying termination by Inotek any time prior to or within 12 months of the change in control, all such employee’s outstanding stock options and RSUs will vest in full and the stock options will become exercisable. Inotek determined that the original awards were expected to vest under their original terms both prior to and after the modification
Share based compensation, incremental expense		0
Accelerated Vesting of Unvested Restricted Stock Units and Stock Options [Member] | Research and Development [Member]
Stockholders Equity [Line Items]
Charge to operations		142,000
Accelerated Vesting of Unvested Restricted Stock Units and Stock Options [Member] | General and Administrative [Member]
Stockholders Equity [Line Items]
Charge to operations		$ 16,000
Restricted Stock Units [Member]
Stockholders Equity [Line Items]
Vesting period			4 years
Amended and Restated 2014 Stock Option and Incentive Plan [Member]
Stockholders Equity [Line Items]
Number of shares reserved for future issuance | shares						207,579
Percentage of outstanding common stock increased to shares available for grant						4.00%
Charge to operations	$ 856,000
Weighted-average fair value of stock option granted | $ / shares						$ 5.72	$ 20.92
Closing price of common stock | $ / shares				$ 24.40		$ 10.44	$ 24.40
Total options exercised | shares							21,107
Number of shares surrendered pursuant to net exercise right | shares							7,530
Unrecognized compensation cost related to non-vested stock options						$ 3,459,000
Stock options, intrinsic value				$ 2,064,000		255,000	$ 2,064,000
Amended and Restated 2014 Stock Option and Incentive Plan [Member] | October 2017 Modification [Member]
Stockholders Equity [Line Items]
Unrecognized compensation cost related to non-vested stock options						$ 462,000
Amended and Restated 2014 Stock Option and Incentive Plan [Member] | Research and Development [Member]
Stockholders Equity [Line Items]
Charge to operations	196,000
Amended and Restated 2014 Stock Option and Incentive Plan [Member] | General and Administrative [Member]
Stockholders Equity [Line Items]
Charge to operations	$ 660,000
Amended and Restated 2014 Stock Option and Incentive Plan [Member] | Restricted Stock Units [Member]
Stockholders Equity [Line Items]
Number of shares granted by board | shares						232,750	117,500
Number of common stock received for contingent right | shares				1
Stock options, terms of vesting						Vesting for these RSUs was based equally on the achievement of two performance-based conditions, subject to continued service through such achievement dates
Number of vesting achievement of performance-based conditions | Milestone				2
Intrinsic fair value, date of grant				$ 3,055,000
Stock-based compensation expense				$ 0
Fair value of grants to be recognized due to change in vesting criteria			$ 717,000
Weighted average grant date fair value per share as of date of modification | $ / shares						$ 4.20
Amended and Restated 2014 Stock Option and Incentive Plan [Member] | Restricted Stock Units [Member] | Executive Officers [Member]
Stockholders Equity [Line Items]
Number of shares granted by board | shares				117,500
Amended and Restated 2014 Stock Option and Incentive Plan [Member] | Subsequent Events [Member]
Stockholders Equity [Line Items]
Number of shares reserved for future issuance | shares								272,227
2004 Stock Option Plan [Member]
Stockholders Equity [Line Items]
Stock-based compensation expense						$ 0	$ 0
Unrecognized compensation cost related to non-vested stock options						0
Stock options, intrinsic value						$ 0
Employee Stock Purchase Plan [Member]
Stockholders Equity [Line Items]
Number of shares reserved for future issuance | shares						600,000
Percentage of outstanding common stock increased to shares available for grant						1.00%
Stock-based compensation expense						$ 6,000	66,000
Number of shares available for issuance | shares						61,494
Percentage of minimum voting power of common stock not eligible to purchase shares						5.00%
Maximum payroll deduction of employee compensation, percentage						10.00%
Discount rate employees purchase shares on offering period						85.00%
Maximum number of shares purchased by an employee | shares						5,000
Maximum worth of stock an employee purchases						$ 25,000
Stock purchased under ESPP | shares						5,971
Gross proceeds from issuance of common stock						$ 35,000	155,000
Common stock withheld pursuant to employee stock purchase plan							$ 155,000
Number of shares issued | shares							6,481
Employee Stock Purchase Plan [Member] | Subsequent Events [Member]
Stockholders Equity [Line Items]
Number of shares reserved for future issuance | shares								6,562