ACQUISITIONS - Summary of Pro Forma Information (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Total Revenues
As reported	$ 371,483us-gaap_SalesRevenueNet	$ 180,202us-gaap_SalesRevenueNet
Pro forma (unaudited)		465,791
Operating Income
As reported	8,455us-gaap_OperatingIncomeLoss	8,053us-gaap_OperatingIncomeLoss
Pro forma (unaudited)		36,176
Net income (loss) applicable to common shareholders
As reported	(11,732)	(19,291)
Pro forma (unaudited)		$ 1,382
Net income (loss) per share applicable to common shareholders
As reported, (in dollars per share)	$ (0.67)us-gaap_EarningsPerShareBasicAndDiluted	$ (1.30)us-gaap_EarningsPerShareBasicAndDiluted
Pro forma (unaudited) (in dollars per share)		$ 0.09

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 45

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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