| **Selected quarterly financial data (Unaudited) (Tables)**       | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **22. Selected quarterly financial data (Unaudited) [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| Schedule of Quarterly Financial Information [Table Text Block]   |  1st Quarter Ended January 31,  2nd Quarter Ended April 30, (in millions, except for per share data and stock price)2012 2011 2012 2011Sales and revenues, net$3,052 $2,743 $3,298 $3,355Manufacturing gross margin(A)(B)310 494 311 597Net income (loss)(C)(140) 6 (162) 88Less: Net income attributable to non-controlling interests13 12 10 14Net income (loss) attributable to Navistar International Corporation(153) (6)(172) 74Earnings (loss) per share attributable to Navistar International Corporation:       Basic$(2.19) $(0.08) $(2.50) $1.01Diluted(2.19) (0.08) (2.50) 0.93Market price range-common stock:       High$45.44 $66.39 $48.18 71.49Low33.74 48.32 32.68 58.49 3rd Quarter Ended July 31,  4th Quarter Ended October 31, (in millions, except for per share data and stock price)2012 2011(D) 2012 2011(D)Sales and revenues, net$3,319 $3,537 $3,279 $4,323Manufacturing gross margin(A)(B)401 560 88 845Net income (loss)(C)96 1,409 (2,756) 275Less: Net income attributable to non-controlling interests12 9 13 20Net income (loss) attributable to Navistar International Corporation84 1,400 (2,769) 255Earnings (loss) per share attributable to Navistar International Corporation:       Basic$1.22 $19.10 $(40.13) $3.52Diluted1.22 18.24 (40.13) 3.48Market price range-common stock:       High$35.25 $70.40 $26.48 $52.36Low20.21 50.05 18.17 30.01_________________________(A)Manufacturing gross margin is calculated by subtracting Costs of products sold from Sales of manufactured products, net. (B)We record adjustments to our product warranty accrual to 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. In the fourth quarter of 2012, we recorded adjustments for changes in estimates of $149 million. The warranty estimation for engines sold in 2012 includes a factor for improvements to the design and manufacturing process that was based on historical experience. In the fourth quarter of 2012, we identified a deviation from historic experience and we recorded an adjustment for a change in estimate to increase the costs accrued for warranty of $28 million for products sold in the first three quarters of 2012.  (C)In the fourth quarter of 2012, we determined that a significant additional valuation allowance on our U.S. deferred tax assets was required, due in part to our current domestic performance, which include continued fourth quarter deterioration and cumulative losses as of October 31, 2012 which included significant fourth quarter warranty charges. As a result we recognized income tax expense of $2 billion for the increase in the valuation allowance. In the fourth quarter of 2012, we also recognized $233 million of income tax expense related to the reversal of income tax benefits recognized in the first, second, and third quarters of 2012. (D)In the fourth quarter of 2011, certain out-of-period adjustments were recorded related to the partial release of the Company's income tax valuation allowance. The adjustments of approximately $61 million primarily related to the classification of a deferred tax item and resulted in the Company recognizing an additional income tax benefit. The Company should have recognized the income tax benefit for this amount in the third quarter of 2011 with the release of a portion of the Company's income tax valuation allowance. Correcting the error was not material to any of the related periods. |

| X                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**nav_A22SelectedQuarterlyFinancialDataUnauditedAbstract**Namespace Prefix:**nav_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Tabular disclosure of the quarterly financial data in the annual financial statements. The disclosure includes financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income (loss) before extraordinary items and cumulative effect of a change in accounting principle and earnings per share data.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a)-(j) -URI http://asc.fasb.org/extlink&oid=20225539&loc=d3e1280-108306
+ Details**Name:**us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |