Income Taxes (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Income Tax Contingency [Line Items]
Valuation allowance	$ 141.0
Net of federal benefit	113.0
Deferred Tax Assets, Net, Current	2.0
Deferred Tax Assets, Net, Noncurrent	$ 2.0
Shareholder's Right Plan [Member]
Income Tax Contingency [Line Items]
Beneficial ownership	4.90%
Internal Revenue Service (IRS) [Member]
Income Tax Contingency [Line Items]
Operating loss carryforward		$ 2,400.0
Washington, Oregon, Idaho, And Montana [Member] | Internal Revenue Service (IRS) [Member]
Income Tax Contingency [Line Items]
Operating loss carryforward		$ 1,000.0