Financing Arrangement (Narrative) (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified				1 Months Ended		1 Months Ended		1 Months Ended	42 Months Ended		1 Months Ended	27 Months Ended
	Jun. 30, 2014	Mar. 31, 2014		Jul. 31, 2011 Convertible Note Hedge	Jul. 14, 2011 Convertible Note Hedge	Jul. 31, 2011 Warrants	Jul. 14, 2011 Warrants	Aug. 31, 2011 Revolving Credit Facility [Member]	Feb. 29, 2016 Revolving Credit Facility [Member]	Aug. 30, 2012 Revolving Credit Facility [Member]	Jul. 31, 2011 Convertible Debt days	Jun. 30, 2016 Convertible Debt	Jun. 30, 2014 Convertible Debt	Jul. 14, 2011 Convertible Debt	Jul. 14, 2011 Convertible Debt Liability Component	Jul. 14, 2011 Convertible Debt Equity Component	Jul. 14, 2011 Convertible Debt
Financing Arrangements
Principal amount	$ 633,000,000	$ 633,000,000											$ 632,500,000
Contractual interest rate of 0.75% Convertible Senior Notes due 2016														0.75%			0.75%
Convertible Senior Notes due description											2016
0.75% Convertible Senior Notes due 2016 maturity date								Feb. 29, 2016			Jul. 15, 2016
Conversion rate of Notes											31.5075
Face amount of Notes														1,000
Debt Instrument, Convertible, Conversion Price														$ 31.74
Number of trading days greater than or equal to the initial conversion price											20
Consecutive trading days under conversion trigger											30
Trigger price as percent of conversion price											130.00%
Trigger price											$ 41.26
Number of trading day that trading price falls below 98% of last reported sales price multiplied by conversion rate											5
Consecutive trading days under conversion trigger, trading price											10
Debt trading price as a percentage of stock price times conversion rate											98.00%
Convertible Senior Notes, Carrying Value	586,000,000	580,000,000	[1]												525,000,000
Effective interest rate														4.54%
Debt issuance costs										2,000,000				15,000,000	13,000,000	2,000,000
Debt instrument remaining discount amortization period												2 years 0 months
Shares covered by Hedge Transactions					19.9
Strike price for convertible note hedge					$ 31.74
Amount paid for Convertible Note Hedge				107,000,000
Shares covered by warrants issuance							19.9
Strike price of warrants							41.14
Proceeds from Warrants transaction						65,000,000
Line of Credit Facility
Line of Credit Facility, Maximum Borrowing Capacity										500,000,000
Line of Credit Facility Term									3 years 6 months
Option To Request Additional Commitments On Credit Facility										$ 250,000,000

[1] Derived from audited consolidated financial statements.