Restructuring Charges Length Of Payment Period

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

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-Name Accounting Standards Codification

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 46

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 3

-Subparagraph (b)

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- Definition

Amount expected to be charged against earnings in the current and future periods for the specified restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

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-Topic 420

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-Subparagraph (SAB Topic 5.P.4(b))

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 95-3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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- Definition

Amount charged against earnings in the period for incurred and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding asset retirement obligations.

+ References

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 95-3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Staff Accounting Bulletin (SAB)

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- Definition

Amount of any reversal and other adjustment made during the period to the amount of a previously accrued liability for a specified type of restructuring cost, excluding adjustments for costs incurred during the period, costs settled during the period, and foreign currency translation adjustments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

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-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Reserve increase representing the amount charged against earnings in the period for a specified incurred and estimated type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 146

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Topic 420

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- Definition

Amount of cash paid in the period to fully or partially settle a specified, previously accrued type of restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b)(2))

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-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 95-3

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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Restructuring (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended				3 Months Ended	18 Months Ended	3 Months Ended							6 Months Ended	18 Months Ended	12 Months Ended		3 Months Ended	18 Months Ended	12 Months Ended		6 Months Ended		18 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended					12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended
	Apr. 30, 2012	Apr. 30, 2011	Apr. 30, 2012	Apr. 30, 2011	Apr. 30, 2012 Fort Wayne, Springfield, Chatham and Custom Products [Member]	Apr. 30, 2011 Fort Wayne, Springfield, Chatham and Custom Products [Member]	Apr. 30, 2012 Fort Wayne And Springfield [Member] Truck [Member]	Apr. 30, 2012 Fort Wayne And Springfield [Member] Truck [Member]	Apr. 30, 2012 Chatham [Member] Truck [Member] Minimum [Member]	Apr. 30, 2012 Chatham [Member] Truck [Member] Maximum [Member]	Apr. 30, 2012 Custom Products [Member] Truck [Member]	Jul. 31, 2011 Custom Products [Member] Truck [Member]	Apr. 30, 2012 Custom Products [Member] Parts [Member]	Apr. 30, 2012 Facility Relocation, Expansion and Development [Member] Minimum [Member]	Apr. 30, 2012 Facility Relocation, Expansion and Development [Member] Maximum [Member]	Apr. 30, 2012 Employee Termination Charges [Member] Fort Wayne, Springfield, Chatham and Custom Products [Member]	Apr. 30, 2012 Employee Termination Charges [Member] Fort Wayne And Springfield [Member] Truck [Member]	Apr. 30, 2012 Employee Termination Charges [Member] Chatham [Member] Truck [Member]	Apr. 30, 2012 Employee Termination Charges [Member] Custom Products [Member] Truck [Member]	Apr. 30, 2011 Employee Termination Charges [Member] Location Springfield Assembly Plant [Member] Truck [Member]	Apr. 30, 2012 Pension and Other Postretirement Contractual Termination Benefits [Member] Fort Wayne And Springfield [Member] Truck [Member]	Apr. 30, 2012 Pension and Other Postretirement Contractual Termination Benefits [Member] Chatham [Member] Truck [Member]	Apr. 30, 2012 Pension and Other Postretirement Contractual Termination Benefits [Member] Custom Products [Member] Truck [Member]	Apr. 30, 2012 Employee Relocation Costs [Member] Fort Wayne, Springfield, Chatham and Custom Products [Member]	Apr. 30, 2011 Employee Relocation Costs [Member] Fort Wayne, Springfield, Chatham and Custom Products [Member]	Apr. 30, 2012 Employee Relocation Costs [Member] Fort Wayne And Springfield [Member] Truck [Member]	Jul. 31, 2011 Lease Vacancy [Member] [Domain] Warrenville [Member] Truck [Member]	Apr. 30, 2012 Lease Vacancy [Member] [Domain] Fort Wayne, Springfield, Chatham and Custom Products [Member]	Jul. 31, 2011 Lease Vacancy fair value [Member] [Domain] Warrenville [Member] Truck [Member]	Jul. 31, 2011 Accrued Rent Expense, Reversal [Domain] Warrenville [Member] Truck [Member]	Jul. 31, 2011 Facility Closing [Member] Chatham [Member] Truck [Member]	Oct. 31, 2011 Facility Closing [Member] Custom Products [Member] Truck [Member]	Jul. 31, 2011 Facility Closing [Member] Custom Products [Member] Truck [Member]	Apr. 30, 2012 Facility Closing [Member] Custom Products [Member] Truck [Member]	Apr. 30, 2012 Other Contractual Costs [Member] Fort Wayne, Springfield, Chatham and Custom Products [Member]	Apr. 30, 2012 Other Contractual Costs [Member] Chatham [Member] Truck [Member]	Apr. 30, 2011 Ford [Member] Employee Termination Charges [Member] Location IEP And ICC [Member]	Apr. 30, 2012 Tax Exempt Bond [Member] Manufacturing Operations [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve					$ 46	$ 18										$ 26								$ 0	$ 0			$ 18							$ 2		$ 18
Debt Instrument, Interest Rate, Stated Percentage																																						6.50%
Restructuring charges (benefit)	20	2	20	24			19	32									13	7	6	4	7	33	4			12	16		19	3	48	5	5	10		8
Expected restructuring and related charges									30	70				45	65
Impairment of Intangible Assets (Excluding Goodwill)	38	0	38	0							28	51	10
Restructuring Charges Length Of Payment Period											2 years
Restructuring Reserve [Roll Forward]
Restructuring liability, balance at beginning of period					39	5										31								0	0			0							8		5
Additions					26	18										2								4	1			19							1		17
Payments					(16)	(5)										(4)								(4)	(1)			(1)							(7)		(4)
Adjustments					(3)											(3)								0				0							0		0
Restructuring liability, balance at end of period					$ 46	$ 18										$ 26								$ 0	$ 0			$ 18							$ 2		$ 18