Finance Receivables, Net (Details) - USD ($) $ in Millions		3 Months Ended		12 Months Ended
		Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross receivables		$ 3,690		$ 3,865
Unearned income		(403)		(425)
Subtotal		3,287		3,440
Residual values		0		0
Allowance for doubtful accounts		(146)	$ (93)	(89)	$ (92)
Finance receivables, net		3,141		3,351
Less: Billed portion of finance receivables, net		108		111
Less: Current portion of finance receivables not billed, net		1,104		1,158
Finance receivables due after one year, net	[1]	$ 1,929		$ 2,082
Finance receivables lease portfolio -low - years		2 years
Finance lease portfolio average maturity - high - years		3 years
Charge-offs		$ (8)	(8)
Credit Concentration Risk | Financing Receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Concentration risk (percentage)		4.40%		2.60%
EMEA
Financing Receivable, Allowance for Credit Loss [Line Items]
Subtotal		$ 1,132		$ 1,192
Allowance for doubtful accounts		(40)	(28)	$ (19)	$ (27)
Charge-offs		$ (4)	$ (3)

[1] Allowances at March 31, 2020 determined in accordance with ASU 2016-13 adopted effective January 1, 2020 - refer to Notes 2, 8 and 9 for additional information.