Financing Receivables (Details 2) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2016 USD ($) PortfolioSegment ClassOfFinancingReceivable	Dec. 31, 2015 USD ($)
Financing Receivables
Total Financing Receivables	$ 18,959	$ 19,945
Collectively evaluated for impairment	18,409	19,406
Individually evaluated for impairment	550	539
Allowance for Credit Losses
Allowance for credit losses, beginning balance	590	561
Write-offs	(19)	(62)
Provision	80	141
Other	14	(51)
Allowance for credit losses, ending balance	666	590
Collectively evaluated for impairment	144	79
Individually evaluated for impairment	$ 522	511
Number of portfolio segments | PortfolioSegment	2
Number of classes of financing receivable | ClassOfFinancingReceivable	2
Major Markets
Financing Receivables
Total Financing Receivables	$ 14,495	15,256
Collectively evaluated for impairment	14,404	15,180
Individually evaluated for impairment	92	76
Allowance for Credit Losses
Allowance for credit losses, beginning balance	109	111
Write-offs	(1)	(14)
Provision	6	20
Other	4	(8)
Allowance for credit losses, ending balance	118	109
Collectively evaluated for impairment	39	43
Individually evaluated for impairment	79	65
Growth Markets
Financing Receivables
Total Financing Receivables	4,463	4,689
Collectively evaluated for impairment	4,005	4,227
Individually evaluated for impairment	458	462
Allowance for Credit Losses
Allowance for credit losses, beginning balance	481	450
Write-offs	(17)	(48)
Provision	74	122
Other	10	(43)
Allowance for credit losses, ending balance	548	481
Collectively evaluated for impairment	105	36
Individually evaluated for impairment	443	445
Lease receivables
Financing Receivables
Total Financing Receivables	7,027	7,041
Allowance for Credit Losses
Allowance for credit losses, beginning balance	213	165
Allowance for credit losses, ending balance	246	213
Lease receivables | Major Markets
Financing Receivables
Total Financing Receivables	5,461	5,517
Allowance for Credit Losses
Allowance for credit losses, beginning balance	25	32
Allowance for credit losses, ending balance	32	25
Lease receivables | Growth Markets
Financing Receivables
Total Financing Receivables	1,566	1,524
Allowance for Credit Losses
Allowance for credit losses, beginning balance	188	133
Allowance for credit losses, ending balance	214	188
Loan receivables
Financing Receivables
Total Financing Receivables	11,931	12,904
Allowance for Credit Losses
Allowance for credit losses, beginning balance	377	396
Allowance for credit losses, ending balance	420	377
Loan receivables | Major Markets
Financing Receivables
Total Financing Receivables	9,034	9,739
Allowance for Credit Losses
Allowance for credit losses, beginning balance	83	79
Allowance for credit losses, ending balance	86	83
Loan receivables | Growth Markets
Financing Receivables
Total Financing Receivables	2,897	3,165
Allowance for Credit Losses
Allowance for credit losses, beginning balance	293	317
Allowance for credit losses, ending balance	$ 334	$ 293