Commitments and Contingent Liabilities - Environmental Loss Contingencies (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Accrual for Environmental Loss Contingencies
Environmental liability, beginning balance	$ 6,128
Additions to environmental obligations	54
Environmental obligations utilized	(114)
Environmental liability, ending balance	$ 6,068

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

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Amount of expense for newly incurred environmental loss contingencies. Includes, but is not limited to, remediation expense and interest accretion.

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Amount of cash outflow to settle environmental loss contingencies.

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