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Allowance and Other Reserves - Narrative (Details) $ in Millions | Dec. 31, 2020 USD ($) asset | Jan. 01, 2020 USD ($)
--- | --- | ---
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Number of assets | asset | 3 |
Land Operations | First security, generated in 2008 |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Amortized cost basis of financing receivable | $ 1.6 | $ 1.6
Land Operations | Second security, generated in 2016 |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Amortized cost basis of financing receivable | 11.1 | 13.5
Land Operations | Third security, generated in 2017 |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |
Amortized cost basis of financing receivable | $ 2.7 | $ 2.6

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