ACQUISITIONS - Pro Forma (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Business Combinations [Abstract]
Revenue from services	$ 696,475	$ 685,749
Net income attributable to common shareholders	$ 13,165	$ 18,096
Net income per share attributable to common shareholders - Basic (in dollars per share)	$ 0.38	$ 0.56
Net income per share attributable to common shareholders - Diluted (in dollars per share)	$ 0.34	$ 0.02

The pro forma basic net income per share for a 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
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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- Definition

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.

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

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No definition available.

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