Consolidated Statements of Income and Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Income Statement [Abstract]
Net sales	$ 8,167,933	$ 7,864,758	$ 8,328,909
Cost of products sold	7,049,726	6,891,664	7,164,243
Gross profit	1,118,207	973,094	1,164,666
Selling, general and administrative expenses	634,119	536,044	477,444
Amortization of intangible assets	97,234	75,638	55,118
Impairment charges	10,057	0	0
Acquisition-related costs	0	114,866	0
Interest income	3,116	8,080	2,148
Interest expense	107,322	68,112	5,187
Other income (expense), net	305	(1,848)	3,964
Income before income taxes	272,896	184,666	633,029
Income taxes	51,512	52,201	202,878
Net income	221,384	132,465	430,151
Less: net (loss) attributable to non-controlling interests	(1,590)	(810)	0
Net income attributable to Thor Industries, Inc.	$ 222,974	$ 133,275	$ 430,151
Weighted-average common shares outstanding:
Basic - weighted-average common shares outstanding (in shares)	55,172,694	53,905,667	52,674,161
Diluted - weighted-average common shares outstanding (in shares)	55,397,376	54,026,686	52,853,360
Earnings per common share:
Basic - earnings per common share (in dollars per share)	$ 4.04	$ 2.47	$ 8.17
Diluted - earnings per common share (in dollars per share)	$ 4.02	$ 2.47	$ 8.14
Comprehensive income:
Net income	$ 221,384	$ 132,465	$ 430,151
Other comprehensive income (loss), net of tax
Foreign currency translation gain (loss), net of tax	92,735	(47,078)	0
Unrealized (loss) on derivatives, net of tax	(9,351)	(9,472)	0
Other income (loss), net of tax	352	(1,048)	0
Total other comprehensive income (loss), net of tax	83,736	(57,598)	0
Total comprehensive income	305,120	74,867	430,151
Comprehensive (loss) attributable to non-controlling interest	(1,851)	(1,404)	0
Comprehensive income attributable to Thor Industries, Inc.	$ 306,971	$ 76,271	$ 430,151