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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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Unrecognized cost of unvested share-based compensation awards.

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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 share-based awards, other than options, awarded to employees as compensation.

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The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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

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Stock-Based Compensation - Additional Information (Detail)			3 Months Ended		9 Months Ended
	May. 11, 2015 Director shares	Oct. 07, 2014 Director shares	Sep. 30, 2015 USD ($) shares	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) shares	Sep. 30, 2014 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense					$ 100,000	$ 100,000
Unrecognized compensation cost related to Incentive Units			$ 600,000		$ 600,000
Unrecognized compensation cost related to Incentive Units, weighted-average recognition period					6 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense			100,000	$ 100,000
May Two Thousand Fifteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock expense			$ 200,000		$ 300,000
Common Class C-1 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be issue \| shares			1,000		1,000
Common Class C-2 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be issue \| shares			1,000		1,000
Restricted Stock Issued to Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost			$ 500,000		$ 500,000
Restricted Stock Issued to Directors [Member] \| October Two Thousand Fourteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock issued \| shares		31,115
Number of non employee directors \| Director		7
Stock based compensation expense					300,000
Restricted Stock [Member] \| May Two Thousand Fifteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares of common stock issued \| shares	132,496
Number of non employee directors \| Director	7
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost			5,600,000		5,600,000
Performance Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost			$ 3,700,000		$ 3,700,000
2014 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be issue \| shares			16,000,000		16,000,000
Number of shares are available for future grant \| shares			14,367,022		14,367,022