Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
U.S. federal corporate income tax rate	21.00%	35.00%
Tax Cuts and Jobs Act, Measurement Period Adjustment, Income Tax Expense (Benefit)	$ 1,500,000	$ 33,200,000
Increase (Decrease) in Income Taxes Receivable		1,600,000
Fed Tax On GILTI	0
Increase in carryforward of unused FTCs	109,600,000
Unrecognized tax benefits, interest on income taxes accrued	500,000
Unrecognized tax benefits that would reduce the income tax provision	6,100,000
Valuation allowance	128,365,000	124,036,000
Liability for UTPs	13,315,000	61,182,000
Changes in valuation allowance	$ 4,300,000	$ 120,400,000
Internal Revenue Service (IRS) [Member]
Income Tax Contingency [Line Items]
Statute of limitations to expire during next twelve months	2014
Operating loss carryforwards	$ 107,100,000
Operating loss carryforwards, limitations on use	$ 32,600,000
Federal Income Taxes and State Income Taxes [Member]
Income Tax Contingency [Line Items]
Net operating loss carryforwards, expiration period	2022 to 2034
New York [Member]
Income Tax Contingency [Line Items]
Operating loss carryforwards	$ 1,500,000
Other Tax Carryforward, AMT Tax Credits [Member] | State and Local Jurisdiction [Member]
Income Tax Contingency [Line Items]
Tax credit carryforward	$ 1,300,000