Income Taxes Summary of Operating Loss Carryforwards (Details) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2012	Jan. 31, 2011
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	$ 2,418,707	$ 1,965,556
U.S. Federal NOLs [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	946,997	672,427
U.S. State NOLs [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	610,284	421,228
Foreign NOLs [Member]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards	$ 861,426	$ 871,901