Inventories (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Mar. 31, 2012
Schedule of Inventory [Line Items]
Net merchandise inventory	$ 438,378	$ 282,409
Video [Member]
Schedule of Inventory [Line Items]
Net merchandise inventory	182,257	102,703
Appliances [Member]
Schedule of Inventory [Line Items]
Net merchandise inventory	138,612	88,191
Computing and mobile phones [Member]
Schedule of Inventory [Line Items]
Net merchandise inventory	49,866	41,615
Other [Member]
Schedule of Inventory [Line Items]
Net merchandise inventory	$ 67,643	$ 49,900