Restructuring Programs (Details) $ in Millions		3 Months Ended
		Mar. 31, 2018 USD ($) Employees	Mar. 31, 2017 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring, Net Current Period Charges	[1]	$ 28
Restructuring Charges		$ 36
Restructuring and Related Cost, Expected Number of Positions Eliminated (approximately) | Employees		400
Reversals		$ (8)
Restructuring Reserve [Roll Forward]
Balance at beginning of period		109
Provision		36
Reversals		(8)
Net Current Period Charges	[1]	28
Charges against reserve and currency		(52)	$ (57)
Balance at end of period		85
Reconciliation To Consolidated Statements Of Cash Flows [Abstract]
Charges against reserve and currency		(52)	(57)
Effects of foreign currency and other non-cash items		(2)	(1)
Restructuring Cash Payments		(54)	$ (58)
Severance and Related Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, Net Current Period Charges	[1]	16
Restructuring Charges		24
Reversals		(8)
Restructuring Reserve [Roll Forward]
Balance at beginning of period		108
Provision		24
Reversals		(8)
Net Current Period Charges	[1]	16
Charges against reserve and currency		(41)
Balance at end of period		83
Reconciliation To Consolidated Statements Of Cash Flows [Abstract]
Charges against reserve and currency		(41)
Lease Cancellation and Other Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, Net Current Period Charges	[1]	12
Restructuring Charges		12
Reversals		0
Restructuring Reserve [Roll Forward]
Balance at beginning of period		1
Provision		12
Reversals		0
Net Current Period Charges	[1]	12
Charges against reserve and currency		(11)
Balance at end of period		2
Reconciliation To Consolidated Statements Of Cash Flows [Abstract]
Charges against reserve and currency		(11)
Asset Impairments [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring, Net Current Period Charges	[1],[2]	0
Restructuring Charges	[2]	0
Reversals	[2]	0
Restructuring Reserve [Roll Forward]
Balance at beginning of period	[2]	0
Provision	[2]	0
Reversals	[2]	0
Net Current Period Charges	[1],[2]	0
Charges against reserve and currency	[2]	0
Balance at end of period	[2]	0
Reconciliation To Consolidated Statements Of Cash Flows [Abstract]
Charges against reserve and currency	[2]	$ 0

[1] Represents net amount recognized within the Condensed Consolidated Statements of Income for the period shown for restructuring and asset impairments charges.

[2] Charges associated with asset impairments represent the write-down of the related assets to their new cost basis and are recorded concurrently with the recognition of the provision.