Document And Entity Information - shares	6 Months Ended
	Jan. 31, 2019	Feb. 28, 2019
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jan. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Entity Registrant Name	THOR INDUSTRIES INC
Entity Central Index Key	0000730263
Current Fiscal Year End Date	--07-31
Entity Filer Category	Large Accelerated Filer
Trading Symbol	THO
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		55,063,473