Assets Measured at Fair Value Using Significant Unobservable Inputs (Detail) (Level 3, USD $) In Thousands, unless otherwise specified	6 Months Ended
Jan. 31, 2014
Level 3
Fair value measurements Significant unobservable inputs [Line Items]
Beginning Balances	$ 666
Net change in other comprehensive income	34
Sales	(700)
Ending Balances

Name:	tho_FairValueMeasurementsSignificantUnobservableInputsLineItems
Namespace Prefix:	tho_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Fair Value, Measurement with Unobservable Inputs Reconciliation, Nonrecurring Basis, Asset Value

+ References

No definition available.

+ Details

Name:	tho_FairValueMeasurementWithUnobservableInputsReconciliationNonrecurringBasisAssetValue
Namespace Prefix:	tho_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1a)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration