Stockholders' Equity (Narrative) (Details)	3 Months Ended
	Sep. 30, 2015 USD ($) $ / shares shares	Sep. 30, 2014 USD ($) shares	Jun. 30, 2015 USD ($) $ / shares shares	Apr. 30, 1997 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cost of common shares repurchased | $	$ 62,000,000	$ 42,900,000
Common shares repurchased	1,200,000	800,000
Additional shares that can be repurchased under the approved share repurchase program	14,300,000
Number of shares repurchased pursuant to the repurchase program	40,386,234		39,186,234
Cost of shares repurchased pursuant to the repurchase program | $	$ 1,506,542,000		$ 1,444,554,000
Preferred stock, shares authorized	2,000,000		2,000,000	2,000,000
Preferred stock at par value | $ / shares	$ 0.01		$ 0.01	$ 0.01
Preferred stock, shares issued	0		0
Preferred stock, shares outstanding	0		0
Stock option and restricted stock units expiration period	7 years
Common stock authorized for issuance	43,700,000
Number of securities remaining available for future issuance	13,800,000
Reduction in the number of shares of common stock available for issuance	2.8
Maximum number of shares subject to awards granted	3,000,000
Number of common stock shares granted in participant's initial year of hiring	4,500,000
Unrecognized compensation costs related to unvested stock-based compensation arrangements | $	$ 57,100,000
Expected weighted average period of unrecognized compensation costs related to unvested stock-based compensation arrangements	2 years
Aggregate intrinsic value of the stock-based compensation arrangements outstanding | $	$ 168,500,000
Aggregate intrinsic value of the stock-based compensation arrangements exercisable | $	46,300,000
Aggregate intrinsic value of the options exercised | $	$ 8,900,000	$ 9,700,000
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities remaining available for future issuance	1,500,000
Percentage of purchase price of common stock lower than the fair market value of common stock on the date of grant	85.00%
Percentage of purchase price of common stock lower than the fair market value of common stock on the date of purchase	85.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options and restricted stock units vesting period	1 year
Minimum [Member] | Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee stock purchase program offering period	3 months
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options and restricted stock units vesting period	4 years
Maximum [Member] | Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee stock purchase program offering period	27 months
Common stock shares subscribed | $	$ 25,000