CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Stockholders' Equity Attributable to Thor	Non-controlling Interests
Beginning balance (in shares) at Jul. 31, 2018		62,765,824				10,070,459
Beginning balance at Jul. 31, 2018	$ 1,937,741	$ 6,277	$ 252,204	$ 2,022,988	$ 0	$ (343,728)	$ 1,937,741	$ 0
Net income	39,974			41,220			41,220	(1,246)
Restricted stock unit activity (in shares)		167,591				55,975
Restricted stock unit activity	(2,597)	$ 16	1,805	0	0	$ (4,418)	(2,597)	0
Cash dividends	(62,664)			(62,664)			(62,664)
Stock compensation expense	14,118		14,118				14,118
Other comprehensive income (loss)	(37,964)				(37,891)		(37,891)	(73)
Cumulative effect of adoption of ASU no. 2014-09, net of tax	(5,450)			(5,450)			(5,450)
Acquisitions (in shares)		2,256,492
Acquisitions	156,375	$ 226	143,942				144,168	12,207
Ending balance (in shares) at Apr. 30, 2019		65,189,907				10,126,434
Ending balance at Apr. 30, 2019	2,039,533	$ 6,519	412,069	1,996,094	(37,891)	$ (348,146)	2,028,645	10,888
Beginning balance (in shares) at Jan. 31, 2019		62,933,415				10,126,434
Beginning balance at Jan. 31, 2019	1,906,931	$ 6,293	263,899	1,984,885	0	$ (348,146)	1,906,931	0
Net income	31,438			32,684			32,684	(1,246)
Restricted stock unit activity	(404)		(404)				(404)
Cash dividends	(21,475)			(21,475)			(21,475)
Stock compensation expense	4,632		4,632				4,632
Other comprehensive income (loss)	(37,964)				(37,891)		(37,891)	(73)
Acquisitions (in shares)		2,256,492
Acquisitions	156,375	$ 226	143,942				144,168	12,207
Ending balance (in shares) at Apr. 30, 2019		65,189,907				10,126,434
Ending balance at Apr. 30, 2019	2,039,533	$ 6,519	412,069	1,996,094	(37,891)	$ (348,146)	2,028,645	10,888
Beginning balance (in shares) at Jul. 31, 2019		65,189,907				10,126,434
Beginning balance at Jul. 31, 2019	2,095,228	$ 6,519	416,382	2,066,674	(57,004)	$ (348,146)	2,084,425	10,803
Net income	101,655			103,806			103,806	(2,151)
Restricted stock unit activity (in shares)		206,624				71,341
Restricted stock unit activity	(2,529)	$ 21	1,213			$ (3,763)	(2,529)
Cash dividends	(66,239)			(66,239)			(66,239)
Stock compensation expense	14,425		14,425				14,425
Other comprehensive income (loss)	(47,863)				(47,220)		(47,220)	(643)
Acquisitions	16,835							16,835
Ending balance (in shares) at Apr. 30, 2020		65,396,531				10,197,775
Ending balance at Apr. 30, 2020	2,111,512	$ 6,540	432,020	2,104,241	(104,224)	$ (351,909)	2,086,668	24,844
Beginning balance (in shares) at Jan. 31, 2020		65,396,531				10,197,775
Beginning balance at Jan. 31, 2020	2,122,334	$ 6,540	427,373	2,102,253	(71,415)	$ (351,909)	2,112,842	9,492
Net income	22,784			24,068			24,068	(1,284)
Restricted stock unit activity	297		297				297
Cash dividends	(22,080)			(22,080)			(22,080)
Stock compensation expense	4,350		4,350				4,350
Other comprehensive income (loss)	(33,008)				(32,809)		(32,809)	(199)
Acquisitions	16,835							16,835
Ending balance (in shares) at Apr. 30, 2020		65,396,531				10,197,775
Ending balance at Apr. 30, 2020	$ 2,111,512	$ 6,540	$ 432,020	$ 2,104,241	$ (104,224)	$ (351,909)	$ 2,086,668	$ 24,844