Lines of Credit and Long-Term Debt - Notes payable and bank lines (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Notes Payable and Long Term Debt
Lines of credit	$ 246	$ 148
Denominated in Euros
Notes Payable and Long Term Debt
Acquisition related debt	$ 44
Interest rate (as a percent)	3.25%
Notes payable to bank
Notes Payable and Long Term Debt
Lines of credit	$ 246
Uncommitted and committed bank lines
Notes Payable and Long Term Debt
Letters of credit outstanding	18
Committed bank line \| Wells Fargo
Notes Payable and Long Term Debt
Maximum capacity	$ 100
Unused commitment fee	0.09%
Outstanding balance	$ 0	0
Committed bank line \| Wells Fargo \| LIBOR
Notes Payable and Long Term Debt
Basis spread on variable rate (as a percent)	0.50%
Uncommitted bank lines
Notes Payable and Long Term Debt
Lines of credit	$ 246	$ 148
Weighted average interest rate (as a percent)	5.79%	7.76%
Uncommitted bank lines \| Denominated in foreign currencies
Notes Payable and Long Term Debt
Lines of credit	$ 189
Uncommitted bank lines \| Foreign subsidiaries \| Denominated in South African Rand
Notes Payable and Long Term Debt
Lines of credit	91
Uncommitted bank lines \| Foreign subsidiaries \| Denominated in Peruvian Sol
Notes Payable and Long Term Debt
Lines of credit	53
Uncommitted bank lines \| Foreign subsidiaries \| Denominated in Canadian dollars
Notes Payable and Long Term Debt
Lines of credit	24
Uncommitted bank lines \| Foreign subsidiaries \| Denominated in Zambian kwacha
Notes Payable and Long Term Debt
Lines of credit	$ 19

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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