OPERATING SEGMENTS (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Revenue, Property and Equipment and Intangible Assets Outside of the United States
Total revenue	$ 42,899	$ 33,013
Total long- lived assets	152,855		150,563
United States
Revenue, Property and Equipment and Intangible Assets Outside of the United States
Total revenue	31,398	24,599
Total long- lived assets	85,080		81,605
Canada
Revenue, Property and Equipment and Intangible Assets Outside of the United States
Total revenue	11,501	8,414
Total long- lived assets	$ 67,775		$ 68,958