Debt (Narrative) (Details) (USD $)	3 Months Ended						3 Months Ended					3 Months Ended											1 Months Ended
	Oct. 31, 2012	Jul. 31, 2012	Jan. 31, 2012	Jul. 31, 2012 Manufacturing Operations [Member]	Oct. 31, 2011 Manufacturing Operations [Member]	Jan. 31, 2012 Manufacturing Operations [Member] Promissory Note With Lessor In Cherokee, Alabama [Member]	Jul. 31, 2012 Manufacturing Operations [Member] Senior Notes [Member]	Nov. 02, 2011 Manufacturing Operations [Member] Senior Notes [Member]	Oct. 31, 2011 Manufacturing Operations [Member] Senior Notes [Member]	Jul. 31, 2012 Manufacturing Operations [Member] Convertible Subordinated Debt [Member]	Oct. 31, 2011 Manufacturing Operations [Member] Convertible Subordinated Debt [Member]	Oct. 31, 2012 Manufacturing Operations [Member] Asset-Based Credit Facility [Member]	Jul. 31, 2012 Manufacturing Operations [Member] Asset-Based Credit Facility [Member]	Jun. 05, 2012 Manufacturing Operations [Member] Asset-Based Credit Facility [Member]	Nov. 30, 2011 Manufacturing Operations [Member] Asset-Based Credit Facility [Member]	Oct. 31, 2011 Manufacturing Operations [Member] Asset-Based Credit Facility [Member]	Jul. 31, 2012 Financial Services [Member]	Oct. 31, 2011 Financial Services [Member]	Jul. 31, 2012 Financial Services [Member] Asset-backed Securities [Member]	Dec. 31, 2011 Financial Services [Member] Bank Facility [Member]	Dec. 31, 2011 Financial Services [Member] Term Loan [Member]	Dec. 31, 2011 Financial Services [Member] Revolving Line Of Credit [Member]	Dec. 31, 2011 Installment Payments Set One [Member] Financial Services [Member] Term Loan [Member] Installments	Dec. 31, 2011 Installment Payments Set Two [Member] Financial Services [Member] Term Loan [Member]	Jul. 31, 2012 Maximum [Member] Manufacturing Operations [Member] Senior Notes [Member]	Oct. 31, 2012 Affiliated Entity [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage							8.25%
Debt instrument early redemption amount							$ 100,000,000	$ 50,000,000	$ 50,000,000																$ 50,000,000
Percent of early redemption price equal to principal amount							103.00%
Line of Credit Facility, Maximum Borrowing Capacity																355,000,000				840,000,000						95,000,000
Loans Payable to Bank		502,000,000																	372,000,000		340,000,000
Length of credit term																				5
Long-term Debt				2,146,000,000	1,980,000,000	40,000,000	872,000,000		967,000,000	514,000,000	497,000,000		238,000,000	138,000,000	100,000,000	0	2,266,000,000	2,876,000,000
Restated Asset-based credit agreement principal amount												175,000,000
Line of Credit Facility, Commitment Fee Amount	1,000,000,000	1,000,000,000
Line of Credit Facility, Periodic Payment	2,500,000
Convertible Debt		100,000,000
Dealer Floor Plan VFN Facility	750,000,000	500,000,000
Length of lease term			10
Long-term Debt, Fair Value						58,000,000
Gains (Losses) on Extinguishment of Debt		8,000,000
Debt Instrument, Face Amount																						500,000,000
Debt Instrument, Periodic Payment, Principal																							$ 4,000,000	$ 9,000,000
Debt Instrument, Number Of Installment Payments																							8	11