Commitments and Contingent Liabilities (Narrative) (Details) - USD ($) $ in Thousands		6 Months Ended
	Mar. 13, 2019	Jun. 30, 2019	Dec. 31, 2018
Product Liability Contingency
Litigation settlement amount		$ 46,000
Present value of remedial work		1,100,000
Undiscovered remedial work		1,700,000
Accrual for environmental loss		6,078	$ 6,128
Uprr
Product Liability Contingency
Annual commitment amount		8,000
Uprr
Product Liability Contingency
Litigation settlement amount	$ 50,000
Litigation settlement amount, current		2,000
Litigation settlement amount, non-current		$ 48,000
Payment period (years)		6 years