Stockholders' Equity - Narrative (Details) $ / shares in Units, shares in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 $ / shares shares	May 31, 2015 EUR (€)	Feb. 13, 2015 USD ($)	May 31, 2014 EUR (€)	Aug. 02, 2013 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Preferred stock, shares authorized | shares	0.0
Cash dividend declared (in dollars per share) | $ / shares	$ 2.40	$ 2.07	$ 1.81
Cash dividend paid (in dollars per share) | $ / shares	$ 2.30	$ 2.005	$ 1.745
Cumulative translation adjustment gains (losses) included in accumulated comprehensive income (loss)	$ (1,400,000,000)	$ (1,100,000,000)
Unrecognized pension and other postretirement benefits costs included in accumulated comprehensive income (loss)	405,000,000	$ 379,000,000
Estimated unrecognized benefit cost that will be amortized from accumulated other comprehensive income into net periodic benefit cost next year	$ 55,000,000
2013 Stock Repurchase Program
Defined Benefit Plan Disclosure [Line Items]
Authorized repurchase amount								$ 6,000,000,000
Shares repurchased | shares		14.9	50.4	3.3
Average price of shares repurchased (in dollars per share) | $ / shares		$ 96.84	$ 84.92	$ 81.62
Authorized repurchases remaining		$ 0
2015 Stock Repurchase Program
Defined Benefit Plan Disclosure [Line Items]
Authorized repurchase amount						$ 6,000,000,000
Shares repurchased | shares	18.7	6.1
Average price of shares repurchased (in dollars per share) | $ / shares	$ 107.17	$ 91.78
Authorized repurchases remaining	$ 3,400,000,000
Discontinued Operations | Accumulated Other Comprehensive Income (Loss)
Defined Benefit Plan Disclosure [Line Items]
Pension and other postretirement benefit adjustments reclassified to income			$ 6,000,000
Net investment hedging
Defined Benefit Plan Disclosure [Line Items]
Cumulative translation adjustment gains (losses) included in accumulated comprehensive income (loss)	$ 375,000,000	$ 308,000,000
Euro notes, issued 2014 | Net investment hedging | Euro notes
Defined Benefit Plan Disclosure [Line Items]
Face value of notes | €							€ 1,000,000,000.0
Euro notes, issued 2015 | Net investment hedging | Euro notes
Defined Benefit Plan Disclosure [Line Items]
Face value of notes | €					€ 1,000,000,000.0