Charge Related to Repurchase of Debt

No definition available.

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- Definition

Payments to subsidiary to meet convenant requirement

+ References

No definition available.

+ Details

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- Definition

Shares of Call Options Unwound

+ References

No definition available.

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- Definition

Shares of Warrants Unwound

+ References

No definition available.

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- Definition

This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries.

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-Name Accounting Standards Codification

-Topic 942

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-Subparagraph (SX 210.12-04.(b))

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

+ Details

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Period Type:	instant

- Definition

Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

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-Subparagraph (SX 210.5-02.19(a)(3))

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-Name Regulation S-X (SX)

-Number 210

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-Paragraph 13

-Subparagraph 2

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Conversion Rate

-URI http://asc.fasb.org/extlink&oid=6509012

+ Details

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Balance Type:	na
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

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-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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+ Details

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- Details

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- Definition

The number of issuer's shares to which the option contract is indexed.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 40

-Section 50

-Paragraph 5

-Subparagraph (a)(3)

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Period Type:	instant

- Definition

Exercise or strike price stated in the contract for options indexed to the issuer's equity shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(1)

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Period Type:	duration

- Definition

The cash outflow for derivative instruments during the period, which are classified as investing activities, excluding those designated as hedging instruments.

+ References

No definition available.

+ Details

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- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

+ Details

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- Definition

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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-Paragraph 14

-Subparagraph (b)

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- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

+ Details

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (b)

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-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(i))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph i

-Article 4

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Debt - Narrative (Details) (USD $)	3 Months Ended					1 Months Ended
Debt - Narrative (Details) (USD $)	Jan. 31, 2015	Jul. 31, 2014	Apr. 30, 2014	Jan. 31, 2014	Jan. 31, 2013	Oct. 31, 2009	Oct. 31, 2014
Debt Instrument [Line Items]
Payments to subsidiary to meet convenant requirement	$ 0			$ 0	$ 0
Warrants and Rights Outstanding	2,875,175us-gaap_WarrantsAndRightsOutstanding
Charge Related to Repurchase of Debt			11,000,000nav_ChargeRelatedtoRepurchaseofDebt
Shares of Call Options Unwound			8,026,456nav_SharesofCallOptionsUnwound
Shares of Warrants Unwound	1,939,376nav_SharesofWarrantsUnwound		6,523,319nav_SharesofWarrantsUnwound
Payments of Debt Issuance Costs	4,000,000us-gaap_PaymentsOfDebtIssuanceCosts			3,000,000us-gaap_PaymentsOfDebtIssuanceCosts
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries		125,000,000
Proceeds from issuance of securitized debt	250,000,000			82,000,000
Three Point Zero Percent Senior Subordinated Convertible Notes [Member]
Debt Instrument [Line Items]
Shares of Warrants Unwound	1,939,376		6,523,319
Four Point Seven Five Senior Subordinated Convertible Notes [Member] [Member]
Debt Instrument [Line Items]
Option Indexed to Issuer's Equity, Strike Price	$ 54.07
Debt Instrument, Convertible, Conversion Ratio	18.4946
Financial Services Operations [Member] \| VFN Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount							500,000,000
Financial Services Operations [Member] \| Notes Payable, Other Payables [Member] \| Investor Notes Maturing Two Thousand and Fifteen [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	250,000,000
Financial Services Operations [Member] \| Notes Payable, Other Payables [Member] \| Investor Notes Maturing October Two Thousand Thirteen [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	200,000,000
Manufacturing Operations [Member] \| Convertible Subordinated Debt [Member] \| Three Point Zero Percent Senior Subordinated Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.00%
Repayments of Long-term Debt			404,000,000
Debt Instrument, Face Amount						570,000,000
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 60.14
Proceeds from Issuance of Warrants						87,000,000
Manufacturing Operations [Member] \| Convertible Subordinated Debt [Member] \| Four Point Five Zero Senior Subordinated Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Manufacturing Operations [Member] \| Convertible Subordinated Debt [Member] \| Four Point Seven Five Senior Subordinated Convertible Notes [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.75%
Debt Instrument, Face Amount			411,000,000
Manufacturing Operations [Member] \| Tax Exempt Bond [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.50%
Call Option [Member] \| Manufacturing Operations [Member] \| Convertible Subordinated Debt [Member] \| Three Point Zero Percent Senior Subordinated Convertible Notes [Member]
Debt Instrument [Line Items]
Payments for Derivative Instrument, Investing Activities						125,000,000
Option Indexed to Issuer's Equity, Indexed Shares						11,337,870
Option Indexed to Issuer's Equity, Strike Price						$ 50.27
Convertible Debt Securities [Member] \| Three Point Zero Percent Senior Subordinated Convertible Notes [Member]
Debt Instrument [Line Items]
Option Indexed to Issuer's Equity, Strike Price						$ 50.27
Debt Instrument, Convertible, Conversion Ratio	19.891
Convertible Debt Securities [Member] \| Four Point Five Zero Senior Subordinated Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Conversion Ratio	17.1233
United States Dollars and Mexican Pesos [Member]
Debt Instrument [Line Items]
Long-term Debt	1,800,000,000
United States of America, Dollars
Debt Instrument [Line Items]
Long-term Debt	$ 121,000,000