Equity - Changes in Equity (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 5,530,659	$ 4,650,589	$ 5,267,346	$ 4,578,678
Net income	56,322	241,400	341,857	451,638
Other comprehensive income (loss)	56,701	(225,741)	156,316	(183,399)
Dividends paid	(88,082)	(84,241)	(176,187)	(168,990)
Stock incentive plan activity	13,610	(1,029)	29,907	17,743
Acquisition activity			(29)
Shares purchased at cost	(50,000)	(50,000)	(100,000)	(164,692)
Ending balance	5,519,210	4,530,978	5,519,210	4,530,978
Shareholders’ Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	5,524,940	4,647,281	5,261,649	4,575,255
Net income	56,159	241,305	341,556	451,434
Other comprehensive income (loss)	56,774	(225,672)	156,476	(183,379)
Dividends paid	(88,082)	(84,176)	(176,187)	(168,652)
Stock incentive plan activity	13,610	(1,029)	29,907	17,743
Acquisition activity			0
Shares purchased at cost	(50,000)	(50,000)	(100,000)	(164,692)
Ending balance	5,513,401	4,527,709	5,513,401	4,527,709
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	5,719	3,308	5,697	3,423
Net income	163	95	301	204
Other comprehensive income (loss)	(73)	(69)	(160)	(20)
Dividends paid	0	(65)	0	(338)
Stock incentive plan activity	0	0	0	0
Acquisition activity			(29)
Shares purchased at cost	0	0	0	0
Ending balance	$ 5,809	$ 3,269	$ 5,809	$ 3,269