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Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Contingency [Line Items]
State income tax rate	1.50%	1.10%	0.80%
Federal tax rate	21.00%	35.00%	35.00%
Tax Cuts and Jobs Act of 2017, Maximum Operating Loss Carrybacks and Carryforwards Percentage	80.00%
Tax Cuts and Jobs Act of 2017, Change in Tax Rate, Deferred Tax Liability, Income Tax (Expense) Benefit		$ 2,900,000
Interest or penalties recorded in income statement	$ 0	0	$ 0
Amount accrued for interest or penalties	$ 0	$ 0
Scenario, Plan [Member]
Income Tax Contingency [Line Items]
Federal tax rate	21.00%
New York [Member]
Income Tax Contingency [Line Items]
State income tax rate			6.50%	7.10%
Domestic Country [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	$ 0
Domestic Country [Member] | Minimum [Member]
Income Tax Contingency [Line Items]
Federal income tax years currently open for audits	2015
Domestic Country [Member] | Maximum [Member]
Income Tax Contingency [Line Items]
Federal income tax years currently open for audits	2018
State And Local Jurisdiction [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	$ 0
State And Local Jurisdiction [Member] | Minimum [Member]
Income Tax Contingency [Line Items]
Federal income tax years currently open for audits	2014
State And Local Jurisdiction [Member] | Maximum [Member]
Income Tax Contingency [Line Items]
Federal income tax years currently open for audits	2018

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