Basis of Presentation and Other Information Reclassification of prior period amounts (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2017
Reclassification of prior period amounts [Line Items]
Revenue, equipment rentals, net	$ 1,359	$ 1,212
Depreciation, equipment rentals	1,029	1,136
Proceeds from Sale and Collection of Receivables	0	170
Payments to Acquire Equipment on Lease	1,516	1,817
Net Cash Provided by (Used in) Financing Activities	(1,887)	(295)
Net Cash Provided by (Used in) Investing Activities	(2,468)	$ (4,369)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 4,952		$ 7,063	$ 6,659	$ 4,425