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Summary of Significant Accounting Policies - Additional Information (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2020
Summary Of Significant Accounting Policies [Line Items] |
Cash equivalents maximum maturity period of highly liquid investments | 90 days
Minimum [Member] |
Summary Of Significant Accounting Policies [Line Items] |
Number of business days for related transactions | 1 day
Minimum [Member] | Notes Receivable |
Summary Of Significant Accounting Policies [Line Items] |
Service Period | 3 years
Minimum [Member] | Property, Plant and Equipment |
Summary Of Significant Accounting Policies [Line Items] |
Service Period | 3 years
Maximum [Member] |
Summary Of Significant Accounting Policies [Line Items] |
Number of business days for related transactions | 2 days
Maximum [Member] | Notes Receivable |
Summary Of Significant Accounting Policies [Line Items] |
Service Period | 10 years
Maximum [Member] | Property, Plant and Equipment |
Summary Of Significant Accounting Policies [Line Items] |
Service Period | 7 years
Securities |
Summary Of Significant Accounting Policies [Line Items] |
Number of business days for related transactions | 2 days
Commodities |
Summary Of Significant Accounting Policies [Line Items] |
Number of business days for related transactions | 1 day

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- Definition Cash equivalents maximum maturity period of highly liquid investments. + References No definition available. + Details
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- Definition Summary Of Significant Accounting Policies [Line Items] + References No definition available. + Details
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- Details
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- Details
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- Details
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