Carrying value as of the balance sheet date of payments made in excess of existing cash balances, which will be honored by the bank but reflected as a loan to the entity. Overdrafts generally have a very short time frame for correction or repayment and are therefore more similar to short-term bank financing than trade financing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Topic 470
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Summary of Accounting Policies - Internal Use Software Assets/Accounts Payable (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Capitalized software development costs, net of amortization	$ 79	$ 66
Capitalized Computer Software, Amortization	$ 15	12	$ 13
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite useful life of intangible assets	3 years
Minimum [Member] \| Software Development [Member]
Finite-Lived Intangible Assets [Line Items]
Finite useful life of intangible assets	3 years
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite useful life of intangible assets	50 years
Maximum [Member] \| Software Development [Member]
Finite-Lived Intangible Assets [Line Items]
Finite useful life of intangible assets	12 years
Accounts Payable [Member]
Finite-Lived Intangible Assets [Line Items]
Accounts payable	$ 77	99
Accrued compensation	$ 20	$ 27