Stock Based Compensation - 2015 Omnibus Incentive Plan (Details) - 2015 Plan - shares	1 Months Ended	12 Months Ended
May 31, 2016	Dec. 31, 2018
Stock Based Compensation
Minimum exercise price per share as a percent of fair market value of a share		100.00%
Total number of shares of common stock that may be issued		2,824,317
Number of shares available for future issuance		699,590
Vesting period		4 years
Option to purchase common stock
Stock Based Compensation
Number of shares issued		2,056,891
Restricted Common Stock
Stock Based Compensation
Number of shares issued	62,237	62,237
Vesting period	4 years
Maximum
Stock Based Compensation
Term of stock options		10 years

Represents the minimum exercise price per share as a percent of fair market value of a share.

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- Definition

Description of pertinent provision of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

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