Treasury Stock (Details) (USD $)	3 Months Ended		6 Months Ended		0 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Apr. 30, 2014 Senior Notes Due 2019 [Member]	Apr. 30, 2014 Privately Negotiated Transaction [Member]	Apr. 30, 2014 Purchase From Accelerated Share Repurchase [Member]
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount			$ 5,400,000,000
Stock repurchases, net			(1,500,998,000)	(101,036,000)		(101,000,000)
Available to repurchase common stock			428,300,000
Amount expended on share repurchases in open market transactions	0	39,700,000	0	101,000,000
Stock repurchased during period, value					1,500,000,000		1,400,000,000
Stock repurchased during the period, shares					1,700,000		19,200,000
Stock repurchased during period, percent of all shares included in agreement							8000.00%
Number of shares repurchased		614,750		1,475,250
Average per share price on share repurchases in open market transactions (in dollars per share)		$ 64.53		$ 68.49
Number of shares withheld to satisfy minimum tax withholding obligations	26,460	23,796	394,770	346,334
Payment for tax withholding related to vested stock units	$ 1,600,000	$ 1,600,000	$ 22,800,000	$ 24,800,000