Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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.

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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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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.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Equity Incentive Plans - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Nov. 30, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation	$ 1,301,774	$ 1,229,353	$ 2,394,034	$ 2,159,510
Service Period Stock Options \| Chief Executive Officer
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			4 years
Performance-Vested Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance-vested stock options	488,352		488,352
Performance-vested stock options, weighted average exercise price	$ 10.00		$ 10.00
2006 Stock Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			5 years
Stock options, available for grant	0		0
Total number of unexercised options	14,544		14,544
2010 Stock Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options, available for grant	0		0
Total number of unexercised options	661,523		661,523
2010 Stock Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			2 years
2010 Stock Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			4 years
2014 Omnibus Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options, available for grant	1,938,717		1,938,717		3,979,200
2014 Omnibus Incentive Plan \| Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total number of unexercised options	1,723,481		1,723,481
2014 Omnibus Incentive Plan \| Restricted Stock Units \| Employee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			3 years
2014 Omnibus Incentive Plan \| Restricted Stock Units \| Non-employee Director
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			1 year