Leases (Balance Sheet Information Related to Operating Leases) (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Deferred Charges [Member]
Lessee, Lease, Description [Line Items]
Operating Lease Asset	$ 18,940
Other Accruals and Current Liabilities [Member]
Lessee, Lease, Description [Line Items]
Operating Lease Liability - Current	3,298
Other Deferred Credits [Member]
Lessee, Lease, Description [Line Items]
Operating Lease Liability - Noncurrent	$ 15,434