Inventories - Balance Sheet and Statement of Cash Flows adjustments due to change in accounting method (Details) - USD ($) $ in Thousands	3 Months Ended						12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2021		Jun. 30, 2020		Jun. 30, 2019
Consolidated Balance Sheets
Inventories							$ 2,090,642		$ 1,964,195	[1]
Deferred income taxes - noncurrent liability							553,981		418,851	[1]
Retained earnings							14,915,497		13,643,907	[1]
Consolidated Statements of Cash Flows
Net income	$ 473,239	$ 448,542	$ 320,111	$ 372,712	$ 202,049	$ 338,094	1,746,861	[2]	1,202,332	[2],[3]	1,525,083	[2],[4]
Deferred income taxes							(51,500)		12,290	[3]	36,435	[3]
Inventories							(85,597)		206,937	[3]	(67,867)	[3]
Previously Reported
Consolidated Balance Sheets
Inventories							1,926,263		1,814,631
Deferred income taxes - noncurrent liability							516,831		382,528
Retained earnings							14,788,268		13,530,666
Consolidated Statements of Cash Flows
Net income	471,733	447,497	321,717	367,369	204,598	339,041	1,732,873		1,206,703		1,512,931
Deferred income taxes							(52,327)		13,692		32,537
Inventories							(70,782)		201,164		(51,817)
Effect of Change
Consolidated Balance Sheets
Inventories							164,379		149,564
Deferred income taxes - noncurrent liability							37,150		36,323
Retained earnings							127,229		113,241
Consolidated Statements of Cash Flows
Net income	$ 1,506	$ 1,045	$ (1,606)	$ 5,343	$ (2,549)	$ (947)	13,988		(4,371)		12,152
Deferred income taxes							827		(1,402)		3,898
Inventories							$ (14,815)		$ 5,773		$ (16,050)

[1] *Year ended June 30, 2020 amounts have been adjusted to reflect the change in inventory accounting method, as described in Notes 1 and 7 to the Consolidated Financial Statements.

[2] *The balances at June 30, 2018 and the year ended June 30, 2020 and 2019 amounts have been revised to reflect the change in inventory accounting method, as described in Notes 1 and 7 to the consolidated financial statements.

[3] *Years ended June 30, 2020 and 2019 amounts have been adjusted to reflect the change in inventory accounting method, as described in Notes 1 and 7 to the Consolidated Financial Statements.

[4] *Years ended June 30, 2020 and 2019 amounts have been adjusted to reflect the change in inventory accounting method, as described in Notes 1 and 7 to the Consolidated Financial Statements.