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Financial Instruments (Narrative) (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021
Unsecured Notes Two | Revolving Credit Facility |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Drawn down amount under credit facility | $ 25,000,000 |
Unsecured notes |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt instrument, face amount | $ 375,000,000 | $ 375,000,000

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