SEGMENT REPORTING, ASSETS AND LIABILITIES (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Property and equipment, net	$ 87,627	$ 73,753
Goodwill	1,249,945	1,138,805	$ 718,587
Reconciliation of operating segment assets to total assets [Abstract]
Total assets	2,090,736	2,083,682
Reconciliation of operating segment liabilities to total liabilities [Abstract]
Total liabilities	580,778	570,136
North America [Member]
Segment Reporting Information [Line Items]
Property and equipment, net	85,236	71,209
Goodwill	1,223,668	1,114,363	$ 692,639
International [Member]
Segment Reporting Information [Line Items]
Property and equipment, net	2,391	2,544
Goodwill	26,277	24,442
Operating Segments [Member]
Reconciliation of operating segment assets to total assets [Abstract]
Total assets	2,182,752	2,180,664
Reconciliation of operating segment liabilities to total liabilities [Abstract]
Total liabilities	644,564	640,416
Operating Segments [Member] | North America [Member]
Reconciliation of operating segment assets to total assets [Abstract]
Total assets	2,141,822	2,138,768
Reconciliation of operating segment liabilities to total liabilities [Abstract]
Total liabilities	571,465	564,832
Operating Segments [Member] | International [Member]
Reconciliation of operating segment assets to total assets [Abstract]
Total assets	40,930	41,896
Reconciliation of operating segment liabilities to total liabilities [Abstract]
Total liabilities	73,099	75,584
Consolidation, Eliminations [Member]
Reconciliation of operating segment assets to total assets [Abstract]
Total assets	(18,344)	(18,344)
Intersegment Eliminations [Member]
Reconciliation of operating segment assets to total assets [Abstract]
Total assets	(73,672)	(78,638)
Reconciliation of operating segment liabilities to total liabilities [Abstract]
Total liabilities	$ (63,786)	$ (70,280)