Convertible Senior Notes (Narrative) (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	0 Months Ended	9 Months Ended			0 Months Ended			9 Months Ended		0 Months Ended
	Apr. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Apr. 30, 2014 Purchase From Accelerated Share Repurchase [Member]	May 06, 2014 Senior Notes Due 2019 [Member]	Apr. 30, 2014 Senior Notes Due 2019 [Member]	Sep. 30, 2014 Senior Notes Due 2019 [Member]		May 06, 2014 Senior Notes Due 2019 [Member] Over Allotment Option [Member]	Apr. 30, 2014 Privately Negotiated Transaction [Member]	Sep. 30, 2014 Level 2 [Member] Carrying Value [Member] Senior Notes Due 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount							$ 1,000
Days Of Additional Interest To Remedy Default	270 days
Convertible debt							1,250,000,000
Stated interest rate percentage							0.50%
Additional amount to cover over-allotment						187,500,000
Proceeds from convertible debt		1,415,717,000	0				1,230,000,000			184,900,000
Payments for (proceeds from) hedge, investing activities						10,800,000	71,800,000
Amount used to repurchase stock		1,600,986,000	156,334,000								101,000,000
Stock repurchased during period, value					1,400,000,000		1,500,000,000
Number of days out of 30 that common stock price exceeded conversion price							20 days
Convertible debt, threshold consecutive trading days							30 days
Convertible debt, threshold percentage of stock price trigger							130.00%
Percentage of conversion rate							0.98
Convertible debt, conversion ratio							0.011111
Convertible debt, conversion price (in dollars per share)							$ 90.00
Repurchase price as a percent of principal amount							100.00%
Holder of a percent of principal in event of default (at least)							25.00%
Percentage Trustee May Declare							100.00%
Percent Of Principal And Accrued Interest Due							100.00%
Amortization of debt discount, effective interest method, percent								3.00%
Convertible notes		1,285,092,000		0								1,285,092,000
Equity component								162,872,000	[1]
Deferred tax liability, equity component								$ 8,200,000
Shares Of Common Stock Covered By Note Hedges							13.9
Additional warrant transaction							2.1
Class of warrant or right, exercise price of warrants or rights (in dollars per share)							120

[1] Recorded in the condensed consolidated balance sheet within additional paid-in capital.