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Financial Instruments (Narrative) (Details) | 1 Months Ended |  |
--- | --- | --- | ---
Aug. 31, 2017 USD ($) a | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Number of acres | a | 6 |  |
Proceeds from sale of property | $ 12,200,000 |  |
Promissory note received in sale of land | $ 5,700,000 |  |
Interest rate on promissory note | 3.50% |  |
Unsecured Debt |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Debt instrument, face amount |  | $ 375,000,000 | $ 375,000,000

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- Definition Number of Acres + References No definition available. + Details
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