Number of days after the annual meeting stockholder meeting that the board compensation will be granted.

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The performance target payout over the life of the performance period for performance based awards granted as a percentage of the target amount.

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The period over which performance is evaluated against a target.

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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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- Definition

Description of the deferred compensation arrangement, including fixed amounts and determinable awards, or the method for determining payments and awards, the timing of such payments and awards, and any requisite service or performance criteria, as of the balance sheet date.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

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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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General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

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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 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).

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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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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share-based Compensation - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2016	Apr. 22, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise period of options	10 years
2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant	900,000
Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance target for achievement period	3 years
Non-Employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-employee director compensation grant period	5 days
Minimum [Member] \| Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance target for achievement	0.00%
Maximum [Member] \| Graded and Cliff Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of options	5 years
Maximum [Member] \| Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance target for achievement	150.00%
Stock Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense	$ 8.5
Period of recognition of share-based compensation expense	2 years 1 month 6 days
Share-based compensation expense	$ 1.0	$ 1.2
Stock Compensation Plans [Member] \| 2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum aggregate number of shares	1,550,000
Shares available for grant				922,000
Plan description	As of September 30, 2018, subject to adjustments as provided in the 2015 Plan, the maximum aggregate number of shares of the Company’s common stock that could be issued under the 2015 Plan could not exceed the sum of (i) 1.6 million shares plus (ii) any shares (A) remaining available for the grant of awards as of the 2015 Plan effective date (April 22, 2015) under the 2007 Plan or the 2011 Plan, and/or (B) subject to an award granted under the 2007 Plan or the 2011 Plan, which award is forfeited, cancelled, terminated, expires, or lapses without the issuance of shares or pursuant to which such shares are forfeited. As of the effectiveness of the 2015 Plan (April 22, 2015), there were 922 thousand shares available for grant under the 2015 Plan, inclusive of shares previously available for grant under the 2007 Plan and the 2011 Plan that were rolled over to the 2015 Plan.
Restricted Stock [Member] \| Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance target for achievement period	1 year
Deferred compensation arrangement with individual, description	Each participant in the program is eligible to earn RSAs, subject to performance over a one-year period. Payout under the program can range from 0% to 150% of target based on the achievement of five Company performance metrics and individual performance goals (subject to continued employment and certain other terms and conditions of the program).
Vesting period of options	2 years
Restricted Stock [Member] \| Minimum [Member] \| Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance target for achievement			0.00%
Restricted Stock [Member] \| Maximum [Member] \| Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance target for achievement			150.00%