Note 11 - Other Noncurrent Assets (Details Textual) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
|
| Amortization Expense of Catalyst, Assets | $ 8 | $ 9 | $ 10 |
| X | ||||||||||
- Definition Represents the expense charged against earnings during the period to allocate the costs of catalyst assets over the periods expected to benefit from such costs. No definition available.
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