Commitments, Contingencies and Uncertainties (Future Minimum Payments For Operating Leases) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Leased Assets [Line Items]
Operating Leases, Rent Expense	$ 1,700	$ 1,900	$ 1,800
2017	808
2018	662
2019	666
2020	664
2021	$ 562
Newman Land Lease
Operating Leased Assets [Line Items]
Lease Expiration Date	Jun. 30, 2033
Lessee Leasing Arrangements, Operating Leases, Renewal Term	25 years
Other Property
Operating Leased Assets [Line Items]
Lessee Leasing Arrangements, Operating Leases, Term of Contract	P4Y