Amount for accounts payable to related parties.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Relationship with IBM and Related Party Transactions - Borrowing, Services, and Other Arrangements (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Related party transactions
Interest expense incurred on related party borrowings	$ 35	$ 58	$ 84	$ 131
Accounts payable to related party	931		931		$ 336
IBM
Related party transactions
Selling, general and administrative expense with related party	38	54	72	102
Accounts payable to related party	931		931		$ 336
IBM \| Financing cost \| Debt payable to IBM
Related party transactions
Interest expense incurred on related party borrowings	35	58	84	131
IBM \| Sales of returned equipment \| Other (income) and expense
Related party transactions
Net profit on transaction with related party	$ 19	$ 7	$ 21	$ 9