Financing Receivables - Credit Quality Indicators (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Net recorded investment for each class of receivables, by credit quality indicator
Troubled debt restructurings of financing receivables
Lease receivables | Americas
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	3,465	3,847
Lease receivables | Americas | Aaa - Aa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	385	422
Lease receivables | Americas | A1 - A3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	741	855
Lease receivables | Americas | Baa1 - Baa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	796	980
Lease receivables | Americas | Ba1 - Ba2
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	754	730
Lease receivables | Americas | Ba3 - B1
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	459	443
Lease receivables | Americas | B2 - B3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	298	367
Lease receivables | Americas | Caa - D
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	32	51
Lease receivables | EMEA
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	1,365	1,340
Lease receivables | EMEA | Aaa - Aa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	54	49
Lease receivables | EMEA | A1 - A3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	167	190
Lease receivables | EMEA | Baa1 - Baa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	416	371
Lease receivables | EMEA | Ba1 - Ba2
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	432	448
Lease receivables | EMEA | Ba3 - B1
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	185	192
Lease receivables | EMEA | B2 - B3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	100	77
Lease receivables | EMEA | Caa - D
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	10	13
Lease receivables | Asia Pacific
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	1,132	1,302
Lease receivables | Asia Pacific | Aaa - Aa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	87	68
Lease receivables | Asia Pacific | A1 - A3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	434	544
Lease receivables | Asia Pacific | Baa1 - Baa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	278	337
Lease receivables | Asia Pacific | Ba1 - Ba2
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	184	184
Lease receivables | Asia Pacific | Ba3 - B1
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	88	89
Lease receivables | Asia Pacific | B2 - B3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	52	64
Lease receivables | Asia Pacific | Caa - D
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	8	18
Loan receivables | Americas
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	6,012	6,607
Loan receivables | Americas | Aaa - Aa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	668	724
Loan receivables | Americas | A1 - A3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	1,285	1,469
Loan receivables | Americas | Baa1 - Baa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	1,381	1,683
Loan receivables | Americas | Ba1 - Ba2
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	1,308	1,253
Loan receivables | Americas | Ba3 - B1
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	797	760
Loan receivables | Americas | B2 - B3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	517	630
Loan receivables | Americas | Caa - D
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	55	88
Loan receivables | EMEA
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	3,258	3,545
Loan receivables | EMEA | Aaa - Aa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	128	129
Loan receivables | EMEA | A1 - A3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	400	502
Loan receivables | EMEA | Baa1 - Baa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	994	982
Loan receivables | EMEA | Ba1 - Ba2
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	1,032	1,186
Loan receivables | EMEA | Ba3 - B1
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	443	508
Loan receivables | EMEA | B2 - B3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	239	204
Loan receivables | EMEA | Caa - D
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	23	34
Loan receivables | Asia Pacific
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	2,203	2,303
Loan receivables | Asia Pacific | Aaa - Aa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	169	120
Loan receivables | Asia Pacific | A1 - A3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	845	961
Loan receivables | Asia Pacific | Baa1 - Baa3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	541	596
Loan receivables | Asia Pacific | Ba1 - Ba2
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	358	325
Loan receivables | Asia Pacific | Ba3 - B1
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	172	157
Loan receivables | Asia Pacific | B2 - B3
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	102	113
Loan receivables | Asia Pacific | Caa - D
Net recorded investment for each class of receivables, by credit quality indicator
Financing receivables, net recorded investment	$ 16	$ 31