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Long-Term Debt To Affiliated Trusts (Tables) | 12 Months Ended
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Dec. 31, 2019
Long-Term Debt To Affiliated Trusts [Abstract] |
Schedule of Distribution Rates Paid | The distribution rates paid were as follows during the years ended December 31:
| 2019 |  | 2018 |  | 2017
Low distribution rate | 2.79 | % |  | 2.36 | % |  | 1.81 | %
High distribution rate | 3.61 | % |  | 3.61 | % |  | 2.36 | %
Distribution rate at the end of the year | 2.79 | % |  | 3.61 | % |  | 2.36 | %

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- Definition Long-Term Debt To Affiliated Trusts [Abstract] + References No definition available. + Details
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- Definition Schedule Of Distribution Rates Paid [Table Text Block] + References No definition available. + Details
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