Lines of Credit and Long-Term Debt - Maturities and foreign subsidiary obligations (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Maturities of long-term debt
2021	$ 55
2022	8
2023	7
2024	7
2025	7
Thereafter	$ 679
Foreign subsidiary obligations
Notes Payable and Long Term Debt
Weighted average interest rate (as a percent)	3.51%	3.50%

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
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-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
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