Cat Financial Financing Activities (Details 4) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Recorded Investment, Past Due
Period after which Collection of Future Income is Considered as Not Probable	120 days
Dealer
Financing Receivable, Recorded Investment, Past Due
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	$ 78	$ 78
Finance Receivables | Customer
Financing Receivable, Recorded Investment, Past Due
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	828	807
Finance Receivables | Customer | North America
Financing Receivable, Recorded Investment, Past Due
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	73	77
Finance Receivables | Customer | Europe
Financing Receivable, Recorded Investment, Past Due
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	171	154
Finance Receivables | Customer | Asia Pacific
Financing Receivable, Recorded Investment, Past Due
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	6	4
Finance Receivables | Customer | Mining
Financing Receivable, Recorded Investment, Past Due
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	18	50
Finance Receivables | Customer | Latin America
Financing Receivable, Recorded Investment, Past Due
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	118	106
Finance Receivables | Customer | Caterpillar Power Finance
Financing Receivable, Recorded Investment, Past Due
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest	$ 442	$ 416