SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Supplemental Disclosures of Cash Flow Information
Cash paid for interest	$ 21,325	$ 14,893
Non-cash investing activities:
Purchases of rental equipment included in accounts payable and other accrued liabilities at period end	$ 22,017	$ 24,947