Redeemable Noncontrolling Interest (Details) - Jan. 31, 2015 - Auto Alliance International [Member] - USD ($) $ in Millions	Total
Redeemable Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	50.00%
Payments for Repurchase of Redeemable Noncontrolling Interest	$ 342
Mazda [Member]
Redeemable Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	50.00%