Consolidated Statements Of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Beginning balance at Jun. 30, 2015	$ 562	$ 1,228,795	$ (1,444,554)	$ 1,976,020	$ (173,516)	$ 1,587,307
Beginning balance, shares at Jun. 30, 2015	179,661,000		(39,186,000)
Common stock issued on exercise of options (note 12)	$ 5	26,247				26,252
Common stock issued on exercise of options, shares (note 12)	1,176,000
Common stock issued on vesting of restricted stock units, net of shares withheld for tax (note 12)	$ 3	(12,388)				(12,385)
Common stock issued on vesting of restricted stock units, net of shares withheld for tax, shares (note 12)	619,000
Common stock issued on employee stock purchase plan (note 12)	$ 1	14,081				14,082
Common stock issued on employee stock purchase plan, shares (note 12)	291,000
Treasury stock purchases	$ (8)		$ (102,057)			(102,065)
Treasury stock purchases, shares			(1,900,000)
Stock-based compensation costs		46,503				46,503
Other comprehensive income					(49,142)	(49,142)
Net income				352,409		352,409
Dividends declared				(168,130)		(168,130)
Ending balance at Jun. 30, 2016	$ 563	1,303,238	$ (1,546,611)	2,160,299	(222,658)	1,694,831
Ending balance, shares at Jun. 30, 2016	181,747,000		(41,086,000)
Common stock issued on exercise of options (note 12)	$ 3	22,246				22,249
Common stock issued on exercise of options, shares (note 12)	740,000
Common stock issued on vesting of restricted stock units, net of shares withheld for tax (note 12)	$ 2	(8,159)				(8,157)
Common stock issued on vesting of restricted stock units, net of shares withheld for tax, shares (note 12)	447,000
Common stock issued on employee stock purchase plan (note 12)	$ 1	15,884				15,885
Common stock issued on employee stock purchase plan, shares (note 12)	327,000
Stock-based compensation costs		45,921				45,921
Other comprehensive income					33,599	33,599
Net income				342,284		342,284
Dividends declared				(186,346)		(186,346)
Ending balance at Jun. 30, 2017	$ 569	1,379,130	$ (1,546,611)	2,316,237	(189,059)	1,960,266
Ending balance, shares at Jun. 30, 2017	183,261,000		(41,086,000)
Common stock issued on exercise of options (note 12)	$ 2	18,759				$ 18,761
Common stock issued on exercise of options, shares (note 12)	539,000					538,568
Common stock issued on vesting of restricted stock units, net of shares withheld for tax (note 12)	$ 1	(15,385)				$ (15,384)
Common stock issued on vesting of restricted stock units, net of shares withheld for tax, shares (note 12)	214,000
Common stock issued on employee stock purchase plan (note 12)	$ 1	19,955				19,956
Common stock issued on employee stock purchase plan, shares (note 12)	302,000
Treasury stock purchases	$ (2)		$ (53,801)			(53,803)
Treasury stock purchases, shares			(550,000)
Stock-based compensation costs		48,362				48,362
Other comprehensive income					(35,269)	(35,269)
Net income				315,588		315,588
Dividends declared				(199,497)		(199,497)
Ending balance at Jun. 30, 2018	$ 571	$ 1,450,821	$ (1,600,412)	$ 2,432,328	$ (224,328)	$ 2,058,980
Ending balance, shares at Jun. 30, 2018	184,316,000		(41,636,000)