Commitments and Contingent Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accrual for environmental loss contingencies	$ 30,431	$ 30,608

Total costs accrued as of the balance sheet date for environmental loss contingencies.

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-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
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