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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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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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- Definition

Total distributions to each class of partners (i.e., general, limited and preferred partners).

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Changes in the ownership interest during the period of each class of partners. Partners include general, limited and preferred partners.

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Total change in each class of partners' capital accounts during the year due to unit-based compensation. All partners include general, limited and preferred partners.

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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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Gross number of share options (or share units) granted during the period.

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Amount per share or per unit of equity securities issued by non-development stage entity.

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Allocated Share Based Compensation Expense, Not Expected to Vest

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Number of annual vesting periods for which units are vested equally.

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UNIT BASED COMPENSATION - Narrative (Details)			3 Months Ended		9 Months Ended
UNIT BASED COMPENSATION - Narrative (Details)	May. 15, 2015 USD ($)	Feb. 16, 2015 shares	Sep. 30, 2015 USD ($) $ / shares	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) installment $ / shares shares	Sep. 30, 2014 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit based compensation expense			$ 767,000	$ 0	$ 2,168,000	$ 0
Class A Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-voting Class A unit grants in period \| shares					185,000
Unit based compensation expense			463,000		$ 1,301,000
Allocated Share Based Compensation Expense, Not Expected to Vest			$ 0		$ 19,000
IPO \| Common Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Price per common unit \| $ / shares			$ 17.00		$ 17.00
Phantom Share Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit based compensation expense			$ 304,000		$ 867,000
Grants in period \| shares		415,608
Number of annual vesting periods \| installment					4
Unit based compensation expense, unrecognized			4,000,000		$ 4,000,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition					3 years 3 months 21 days
Partners' capital account, distributions, phantom units			95,000		$ 322,000
Phantom Share Units (PSUs) \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period					1 year
Distribution Equivalent Right
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit based compensation expense			0		$ 5,000
Partners' capital account, distributions, phantom units	$ 219,000		107,000
Partners' capital account, unit-based compensation	$ 16,000		8,000
Increase (decrease) in partners' capital			$ 115,000		$ 235,000