STOCK BASED COMPENSATION PLANS - Nonvested Shares Outstanding (Details) - shares	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restricted Stock
Number of Shares Nonvested Other than Options [Roll Forward]
Nonvested/Outstanding at December 31, 2015	1,334,369
Granted (in shares)	960,532
Vested (in shares)	(770,568)
Forfeited (in shares)	(48,467)
Nonvested/Outstanding at December 31, 2016	1,475,866	1,334,369
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Nonvested/Outstanding December 31, 2015	601,186
Granted (in shares)	380,949	670,256	0
Exercised (in shares)	0
Forfeited (in shares)	0
Expired (in shares)	0
Nonvested/Outstanding December 31, 2016	982,135	601,186
Exercisable at December 31, 2016	230,936
LP Units
Number of Shares Nonvested Other than Options [Roll Forward]
Nonvested/Outstanding at December 31, 2015	504
Granted (in shares)	0
Vested (in shares)	(504)
Forfeited (in shares)	0
Nonvested/Outstanding at December 31, 2016	0	504

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=6415400&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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Subparagraph (c)(2)(iii)(1)
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- Definition

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

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)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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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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