Summary of Significant Accounting Policies - Narrative (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended					12 Months Ended						3 Months Ended
	Oct. 31, 2014	Jul. 31, 2014	Oct. 31, 2013		Jul. 31, 2012	Oct. 31, 2014 segments		Oct. 31, 2013		Oct. 31, 2012		Apr. 30, 2014	Apr. 30, 2013	Oct. 31, 2011
Accounting Policies [Line Items]
Cost of Goods Sold						$ (9,534)		$ (9,761)		$ (11,401)
Foreign Currency Transaction Gain (Loss), before Tax						(21)		(23)		(25)
Net Income (Loss) Attributable to Parent						(619)		(898)		(3,010)
Number Of Segments						4
Goodwill	38		184			38		184		280				319
Indefinite-Lived Intangible Assets (Excluding Goodwill)	34		46			34		46
Goodwill, Impairment Loss						142		81
Sales of manufactured products, net						10,653		10,617		12,527
Depreciation and amortization						332		417		323
Interest expense						314		321		259
Capital expenditures						88	[1]	167	[1]	309	[1]
Proceeds from financed lease obligations						60		294		0
Advertising Expense						39		48		78
Product Warranty Accrual, Preexisting, Increase (Decrease)	(10)	(29)	152		10	55	[2],[3]	404	[2],[3]	404	[2],[3]
Unionized Employees Concentration Risk [Member] | Number Of Employees Hourly Workers [Member]
Accounting Policies [Line Items]
Concentration Risk Number Of Employees	6,100					6,100
concentration risk number of employees percentage	70.00%					70.00%
Unionized Employees Concentration Risk [Member] | Number of Employees Salaried Workers [Member]
Accounting Policies [Line Items]
Concentration Risk Number Of Employees	300					300
concentration risk number of employees percentage	5.00%					5.00%
Brazilian Reporting Unit [Member]
Accounting Policies [Line Items]
Goodwill												142
Indefinite-Lived Intangible Assets (Excluding Goodwill)												43
Goodwill, Impairment Loss			81	[4]		142	[4]			0	[4]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)			0			7				0		7
Warranty Liability Prior Period Adjustment [Member]
Accounting Policies [Line Items]
Cost of Goods Sold						(36)
G E Operating Agreement [Member]
Accounting Policies [Line Items]
Net Income (Loss) Attributable to Parent								(8)
Sales of manufactured products, net								(113)
Depreciation and amortization								37
Interest expense								8
Capital expenditures								184
Proceeds from financed lease obligations								201
North America Truck [Member]
Accounting Policies [Line Items]
Goodwill	0		0			0		0		82				82
Goodwill, Impairment Loss			(77)			0		81					(4)
Depreciation and amortization						212		305		216
Interest expense						0		0		0
Capital expenditures						65	[1]	142	[1]	173	[1]
Product Warranty Expense								161		66
North America Truck [Member] | Field Campaign to address issues in products sold [Member]
Accounting Policies [Line Items]
Product Warranty Expense						13		88		130
North America Truck [Member] | Pre-existing Warranty [Member]
Accounting Policies [Line Items]
Product Warranty Expense								127
Extended Warranty Programs [Member]
Accounting Policies [Line Items]
Deferred Revenue, Revenue Recognized						132		87		63
Deferred Revenue	437		420			437		420		364
Warranty contracts sold in current year [Member] | North America Truck [Member]
Accounting Policies [Line Items]
Product Warranty Expense										19
Product Warranty Accrual [Member] | North America Truck [Member]
Accounting Policies [Line Items]
Product Warranty Expense										$ 47
Building [Member] | Minimum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life						20 years
Building [Member] | Maximum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life						50 years
Leasehold Improvements [Member] | Minimum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life						3 years
Leasehold Improvements [Member] | Maximum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life						20 years
Machinery and Equipment [Member] | Minimum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life						3 years
Machinery and Equipment [Member] | Maximum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life						12 years
Furniture and Fixtures [Member] | Minimum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life						3 years
Furniture and Fixtures [Member] | Maximum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life						15 years
Equipment Leased to Other Party [Member] | Minimum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life						1 year
Equipment Leased to Other Party [Member] | Maximum [Member]
Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life						10 years
Customer Relationships [Member] | Minimum [Member]
Accounting Policies [Line Items]
Finite-Lived Intangible Assets, Remaining Amortization Period						3 years
Customer Relationships [Member] | Maximum [Member]
Accounting Policies [Line Items]
Finite-Lived Intangible Assets, Remaining Amortization Period						15 years
Trademarks [Member]
Accounting Policies [Line Items]
Finite-Lived Intangible Assets, Remaining Amortization Period						20 years
Other Intangible Assets [Member] | Minimum [Member]
Accounting Policies [Line Items]
Finite-Lived Intangible Assets, Remaining Amortization Period						3 years
Other Intangible Assets [Member] | Maximum [Member]
Accounting Policies [Line Items]
Finite-Lived Intangible Assets, Remaining Amortization Period						18 years

[1] Exclusive of purchases of equipment leased to others.

[2] (B)In the first quarter of 2013, we recognized $13 million of charges for adjustments to pre-existing warranties for a specific warranty issue related to component parts from a supplier. Also during the first quarter of 2013, we reached an agreement for reimbursement from this supplier for this amount and other costs previously accrued. As a result of this agreement, we recognized a recovery of $27 million within Costs of products sold and recorded a receivable within Other current assets. In the second quarter of 2013, we recognized a warranty recovery of $13 million within Income (loss) from discontinued operations, net of tax and recorded a receivable within Other current assets.In the third quarter of 2012, we recognized $10 million of adjustments to pre-existing warranties for a specific warranty issue related to component parts from a supplier. Also during the quarter, we reached agreement for reimbursement from such supplier and recognized a recovery for that amount and recorded a receivable within Other current assets.

[3] (A)Adjustments to pre-existing warranties reflect changes in our estimate of warranty costs for products sold in prior periods. Such adjustments typically occur when claims experience deviates from historic and expected trends. Our warranty liability is generally affected by component failure rates, repair costs, and the timing of failures. Future events and circumstances related to these factors could materially change our estimates and require adjustments to our liability. In addition, new product launches require a greater use of judgment in developing estimates until historical experience becomes available. In the first quarter of 2014, we recorded adjustments for changes in estimates of $52 million or $0.64 per diluted share. In the second quarter of 2014, we recorded adjustments for changes in estimates of $42 million, or $0.52 per diluted share. In the third quarter of 2014, we recognized a benefit for adjustments to pre-existing warranties of $(29) million, or $(0.36) per diluted share. Included in the 2014 adjustments is a $36 million correction of prior-period errors, primarily related to pre-existing warranties. For more information on the errors identified, see 2014 Out-of-Period Adjustments. The impact of income taxes on the 2014 adjustments is not material due to our deferred tax valuation allowances on our U.S. deferred tax assets.In the first quarter of 2013, we recorded adjustments for changes in estimates of $40 million or $0.50 per diluted share. In the second quarter of 2013, we recorded adjustments for changes in estimates of $164 million, or $2.04 per diluted share. In the third quarter of 2013, we recorded adjustments for changes in estimates of $48 million, or $0.60 per diluted share. In the fourth quarter of 2013, we recorded adjustments for changes in estimates of $152 million, or $1.89 per diluted share. The impact of income taxes on the 2013 adjustments is not material due to our deferred tax valuation allowances on our U.S. deferred tax assets. In the first quarter of 2012, we recorded adjustments for changes in estimates of $123 million, or $1.76 per diluted share. In the second quarter of 2012, we recorded adjustments for changes in estimates of $104 million, or $1.51 per diluted share. In the fourth quarter of 2012, we recorded adjustments for changes in estimates of $149 million, or $2.16 per diluted share.

[4] (A)For more information, see Note 8, Goodwill and Other Intangible Assets, Net, and includes $4 million related to discontinued operations in 2013.