Financing Receivables - Credit Quality Indicators (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Lease receivables
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	$ 6,833	$ 7,041
Loan receivables
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	11,894	12,904
Major Markets | Lease receivables
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	5,355	5,517
Major Markets | Lease receivables | Aaa - Aa3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	490	538
Major Markets | Lease receivables | A1 - A3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	1,235	1,324
Major Markets | Lease receivables | Baa1 - Baa3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	1,498	1,493
Major Markets | Lease receivables | Ba1 - Ba2
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	1,213	1,214
Major Markets | Lease receivables | Ba3 - B1
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	513	513
Major Markets | Lease receivables | B2 - B3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	372	403
Major Markets | Lease receivables | Caa - D
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	35	33
Major Markets | Loan receivables
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	9,077	9,739
Major Markets | Loan receivables | Aaa - Aa3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	831	949
Major Markets | Loan receivables | A1 - A3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	2,093	2,338
Major Markets | Loan receivables | Baa1 - Baa3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	2,539	2,635
Major Markets | Loan receivables | Ba1 - Ba2
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	2,055	2,143
Major Markets | Loan receivables | Ba3 - B1
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	870	905
Major Markets | Loan receivables | B2 - B3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	631	711
Major Markets | Loan receivables | Caa - D
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	59	59
Growth Markets | Lease receivables
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	1,478	1,524
Growth Markets | Lease receivables | Aaa - Aa3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	41	39
Growth Markets | Lease receivables | A1 - A3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	136	162
Growth Markets | Lease receivables | Baa1 - Baa3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	192	392
Growth Markets | Lease receivables | Ba1 - Ba2
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	359	352
Growth Markets | Lease receivables | Ba3 - B1
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	427	277
Growth Markets | Lease receivables | B2 - B3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	213	215
Growth Markets | Lease receivables | Caa - D
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	109	87
Growth Markets | Loan receivables
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	2,817	3,165
Growth Markets | Loan receivables | Aaa - Aa3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	78	80
Growth Markets | Loan receivables | A1 - A3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	260	336
Growth Markets | Loan receivables | Baa1 - Baa3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	366	813
Growth Markets | Loan receivables | Ba1 - Ba2
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	684	732
Growth Markets | Loan receivables | Ba3 - B1
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	814	576
Growth Markets | Loan receivables | B2 - B3
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	407	447
Growth Markets | Loan receivables | Caa - D
Gross recorded investment for each class of receivables, by credit quality indicator
Financing receivables on a gross basis	$ 209	$ 181