Revenue Revenue - Remaining Performance Obligation (Details) - Operating Segments [Member] - Automotive - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Jan. 01, 2017
Vehicles, parts, and accessories
Revenue Remaining Performance Obligation Expected Timing of Satisfaction [Line Items]
Revenue Performance Obligation Satisfied In Prior Period	$ (259)
Extended service contracts
Revenue Remaining Performance Obligation Expected Timing of Satisfaction [Line Items]
Contract With Customer Liability			$ 3,500
Contract With Customer Liability Revenue Recognized	271	$ 541
RevenueRemainingPerformanceObligation	3,700	3,700
Deferrred cost	239	239
Amortization	14	$ 29
Minimum [Member] | Extended service contracts
Revenue Remaining Performance Obligation Expected Timing of Satisfaction [Line Items]
Revenue remaining performance obligation expected timing of satisfaction period		12 months
Minimum [Member] | Other (a)
Revenue Remaining Performance Obligation Expected Timing of Satisfaction [Line Items]
Revenue remaining performance obligation expected timing of satisfaction period		1 year
Maximum [Member] | Extended service contracts
Revenue Remaining Performance Obligation Expected Timing of Satisfaction [Line Items]
Revenue remaining performance obligation expected timing of satisfaction period		120 months
Maximum [Member] | Other (a)
Revenue Remaining Performance Obligation Expected Timing of Satisfaction [Line Items]
Revenue remaining performance obligation expected timing of satisfaction period		2 years
2017-01-01 [Member] | Extended service contracts
Revenue Remaining Performance Obligation Expected Timing of Satisfaction [Line Items]
Revenue remaining performance obligation expected timing of satisfaction period		1 year
RevenueRemainingPerformanceObligation	550	$ 550
2018-01-01 [Member] | Extended service contracts
Revenue Remaining Performance Obligation Expected Timing of Satisfaction [Line Items]
Revenue remaining performance obligation expected timing of satisfaction period		1 year
RevenueRemainingPerformanceObligation	950	$ 950
2019-01-01 [Member] | Extended service contracts
Revenue Remaining Performance Obligation Expected Timing of Satisfaction [Line Items]
Revenue remaining performance obligation expected timing of satisfaction period		8 years
RevenueRemainingPerformanceObligation	$ 2,200	$ 2,200