Equity - Changes in equity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 6,544,249	$ 6,102,792	$ 6,128,529	$ 5,968,152
Net income	447,497	204,598	769,214	543,639
Other comprehensive income (loss)	258,812	184,999	429,646	113,304
Dividends paid	$ (113,687)	$ (113,672)	$ (227,229)	$ (227,025)
Dividends paid (in USD per share)	$ 0.88	$ 0.88	$ 1.76	$ 1.76
Stock incentive plan activity	$ (14,567)	$ 7,529	$ 22,144	$ 38,176
Acquisition activity		6,255		6,255
Shares purchased at cost		(50,000)		(100,000)
Ending balance	7,122,304	6,342,501	7,122,304	6,342,501
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	90,523	90,523	90,523	90,523
Ending balance	90,523	90,523	90,523	90,523
Additional Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	428,329	464,440	416,585	462,086
Stock incentive plan activity	(43,280)	(8,578)	(31,536)	(6,224)
Ending balance	385,049	455,862	385,049	455,862
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	13,738,533	13,003,084	13,530,666	12,777,538
Net income	447,306	204,474	768,715	543,372
Dividends paid	(113,687)	(113,306)	(227,229)	(226,658)
Ending balance	14,072,152	13,094,252	14,072,152	13,094,252
Accumulated Other Comprehensive (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(2,388,472)	(2,130,594)	(2,558,875)	(2,059,048)
Other comprehensive income (loss)	257,966	184,862	428,369	113,316
Ending balance	(2,130,506)	(1,945,732)	(2,130,506)	(1,945,732)
Treasury Shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(5,339,949)	(5,330,837)	(5,364,916)	(5,309,130)
Stock incentive plan activity	28,713	16,107	53,680	44,400
Shares purchased at cost		(50,000)		(100,000)
Ending balance	(5,311,236)	(5,364,730)	(5,311,236)	(5,364,730)
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	15,285	6,176	14,546	6,183
Net income	191	124	499	267
Other comprehensive income (loss)	846	137	1,277	(12)
Dividends paid		(366)		(367)
Acquisition activity		6,255		6,255
Ending balance	$ 16,322	$ 12,326	$ 16,322	$ 12,326