Stockholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Apr. 30, 1997
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares repurchased under repurchase program	41,800,000	200,000
Cost of common shares repurchased	$ 1,600,000	$ 22,845
Total number of shares repurchased pursuant to the repurchase program	41,836,234		41,836,234
Total cost of shares repurchased pursuant to the repurchase program	$ 1,623,256		$ 1,623,256
Additional shares that can be repurchased under the approved share repurchase program	12,900,000
Preferred stock, shares authorized	2,000,000		2,000,000
Preferred stock at par value	$ 0.01		$ 0.01
Preferred stock, shares issued	0		0
Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares repurchased under repurchase program		200,000
Cost of common shares repurchased		$ 22,844
Series A Junior Participating Preferred Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares authorized				2,000,000.0
Preferred stock at par value				$ 0.01
Preferred stock, shares issued	0		0
Preferred stock, shares outstanding	0		0
2009 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	7 years
Common stock authorized for issuance	51,100,000
Number of securities remaining available for future issuance	16,300,000
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities remaining available for future issuance	2,400,000
Minimum [Member] | 2009 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Maximum [Member] | 2009 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years