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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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- Definition

Financing Receivables, Number of Assets

+ References

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- Definition

Amount, before allowance for credit loss, of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
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