Derivatives and Hedging - Schedule of amounts of derivative gains (losses) recognized in the Consolidated Financial Statements (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Gain (loss) recognized in accumulated other comprehensive income	$ 0	$ 0	$ 9,000,000
Estimated pretax losses currently included within Accumulated Other Comprehensive Loss that will be reclassified to earnings in next twelve months	12,000,000
(Loss) income on financial instruments	(14,000,000)	(24,000,000)	(15,000,000)
Not Designated as Hedging Instrument | Foreign exchange contracts
Derivative [Line Items]
(Loss) income on financial instruments	200,000	8,000,000	18,000,000
Designated as Hedging Instrument | Foreign exchange contracts
Derivative [Line Items]
(Loss) income on financial instruments	18,000,000
Designated as Hedging Instrument | Cash Flow Hedging | Foreign exchange contracts
Derivative [Line Items]
Gain (loss) recognized in accumulated other comprehensive income	(25,000,000)	(9,000,000)	(2,000,000)
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)	(10,000,000)	(17,000,000)	(14,000,000)
Designated as Hedging Instrument | Cash Flow Hedging | Foreign exchange contracts | Compensation and Benefits
Derivative [Line Items]
Gain (loss) recognized in accumulated other comprehensive income	8,000,000	4,000,000	11,000,000
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)	2,000,000	4,000,000	(5,000,000)
Designated as Hedging Instrument | Cash Flow Hedging | Foreign exchange contracts | Other General Expenses
Derivative [Line Items]
Gain (loss) recognized in accumulated other comprehensive income	(13,000,000)	(3,000,000)	(3,000,000)
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)	(4,000,000)	(1,000,000)	3,000,000
Designated as Hedging Instrument | Cash Flow Hedging | Foreign exchange contracts | Interest Expense
Derivative [Line Items]
Gain (loss) recognized in accumulated other comprehensive income	0	0	0
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)	(1,000,000)	(9,000,000)	(10,000,000)
Designated as Hedging Instrument | Cash Flow Hedging | Foreign exchange contracts | Other Income
Derivative [Line Items]
Gain (loss) recognized in accumulated other comprehensive income	(20,000,000)	(10,000,000)	(10,000,000)
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)	$ (7,000,000)	$ (11,000,000)	$ (2,000,000)