Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 485,000
Unrecognized tax benefits	$ 410	$ 410	$ 410	$ 0
Start
Operating Loss Carryforwards [Line Items]
Operating loss expiration period	Jan. 01, 2021
End
Operating Loss Carryforwards [Line Items]
Operating loss expiration period	Dec. 31, 2036