ACCOUNTING POLICIES (Details 4) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 item	Jun. 30, 2012	Dec. 31, 2012
Revenue recognition
Number of principal segments			2
Product delivery period from date of shipment, minimum			1 day
Product delivery period from date of shipment, maximum			8 days
Consignment
Maximum revenue from consignment as a percentage of total net revenues	1.00%	1.00%	1.00%	1.00%
International business
Total revenues from International sales	$ 2,900,000	$ 2,000,000	$ 5,800,000	$ 4,300,000
Ecommerce marketplace channels
Revenue from ecommerce marketplace channels as a percentage of total net revenues	2.00%		3.00%
Revenue from ecommerce marketplace channels as a maximum percentage of total net revenues		1.00%		1.00%
Other businesses
Maximum revenue from other businesses as a percentage of total net revenues	1.00%	1.00%	1.00%	1.00%
Club O loyalty program
Expiration period of Club O reward dollars after expiration of the customer's membership			90 days
Deferred revenue
Likelihood of gift card redemption to be remote, period			36 months
Sales returns allowance
Sales return period for which full refund will be granted			30 days
Sales return period for which reduced refund will be granted			30 days
Sales return received at returns processing facility for which reduced refund will be granted, period			45 days
Allowance for sales returns			6,700,000		10,600,000
Credit card chargeback allowance
Credit card chargeback allowance	76,000		76,000		182,000
Cost of goods sold
Total revenue, net	293,204,000	239,536,000	605,198,000	501,903,000
Total revenue, net (as a percent)	100.00%	100.00%	100.00%	100.00%
Cost of goods sold
Product costs and other cost of goods sold	222,403,000	184,121,000	461,600,000	385,914,000
Fulfillment and related costs	12,962,000	12,246,000	26,823,000	25,312,000
Total cost of goods sold	235,365,000	196,367,000	488,423,000	411,226,000
Product costs and other cost of goods sold (as a percent)	76.00%	77.00%	76.00%	77.00%
Fulfillment and related costs (as a percent)	4.00%	5.00%	4.00%	5.00%
Total cost of goods sold (as a percent)	80.00%	82.00%	81.00%	82.00%
Gross profit	57,839,000	43,169,000	116,775,000	90,677,000
Gross profit (as a percent)	20.00%	18.00%	19.00%	18.00%
Advertising expense
Advertising expense	16,900,000	11,600,000	33,400,000	24,100,000
Prepaid advertising expense	$ 1,300,000		$ 1,300,000		$ 1,200,000
Minimum
International business
Number of countries where entity offers its products to customers	100		100