BUSINESS SEGMENTS (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment reporting information
Revenue, net	$ 480,270,000	$ 391,211,000	$ 388,013,000	$ 398,344,000	$ 470,360,000	$ 352,991,000	$ 332,545,000	$ 341,207,000	$ 1,657,838,000	$ 1,497,103,000	$ 1,304,217,000
Total cost of goods sold	397,161,000	318,760,000	314,356,000	322,907,000	384,980,000	285,933,000	269,920,000	277,211,000	1,353,184,000	1,218,044,000	1,056,557,000
Gross profit	83,109,000	72,451,000	73,657,000	75,437,000	85,380,000	67,058,000	62,625,000	63,996,000	304,654,000	279,059,000	247,660,000
Operating expenses	(86,198,000)	(75,822,000)	(71,575,000)	(71,593,000)	(83,672,000)	(64,703,000)	(60,832,000)	(57,929,000)	(305,188,000)	(267,136,000)	(231,095,000)
Other income (expense), net									3,649,000	1,282,000	(221,000)
Provision (benefit) for income taxes	(1,879,000)	(15,000)	1,849,000	1,940,000	968,000	413,000	433,000	2,590,000	1,895,000	4,404,000	(68,034,000)
Consolidated net income	$ (137,000)	$ (2,617,000)	$ 1,426,000	$ 2,548,000	$ 1,305,000	$ 1,617,000	$ 1,909,000	$ 3,970,000	1,220,000	8,801,000	84,378,000
Direct
Segment reporting information
Revenue, net									137,783,000	147,460,000	156,032,000
Total cost of goods sold									128,077,000	129,253,000	136,282,000
Gross profit									9,706,000	18,207,000	19,750,000
Partner
Segment reporting information
Revenue, net									1,518,125,000	1,349,643,000	1,148,185,000
Total cost of goods sold									1,225,107,000	1,088,791,000	920,275,000
Gross profit									293,018,000	260,852,000	227,910,000
Other
Segment reporting information
Revenue, net									1,930,000	0	0
Total cost of goods sold									0	0	0
Gross profit									1,930,000	0	0
Inter-segment
Segment reporting information
Revenue, net									$ 0	$ 0	$ 0