STOCK BASED COMPENSATION PLANS - Nonvested Shares Outstanding (Details) - shares	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restricted Stock
Number of Shares Nonvested Other than Options [Roll Forward]
Nonvested/Outstanding (in shares)			1,475,865	1,334,369
Granted (in shares)			874,621	960,532
Vested (in shares)			(1,425,490)	(274,842)
Forfeited (in shares)			(10,000)	(48,467)
Nonvested/Outstanding (in shares)	914,996	1,971,592	914,996	1,971,592
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Nonvested/Outstanding (in shares)			982,135	601,186
Granted (in shares)	0	0	0	380,949
Exercised (in shares)			0	0
Forfeited (in shares)			0	0
Expired (in shares)			0	0
Nonvested/Outstanding (in shares)	982,135	982,135	982,135	982,135
Exercisable (in shares)	752,017	230,936	752,017	230,936
LP Units
Number of Shares Nonvested Other than Options [Roll Forward]
Nonvested/Outstanding (in shares)				504
Granted (in shares)				0
Vested (in shares)				(504)
Forfeited (in shares)				0
Nonvested/Outstanding (in shares)		0		0

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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).

+ References

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB
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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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-Publisher FASB
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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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

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Number of options outstanding, including both vested and non-vested options.

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Number of non-vested options forfeited.

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Number of share options (or share units) exercised during the current period.

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