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Income Taxes (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Federal tax rate		21.00%	21.00%	35.00%
Tax Cuts and Jobs Act of 2017, maximum operating loss 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			$ 2,900,000
Interest or penalties recorded in income statement		$ 0	$ 0	$ 0
Amounts accrued for interest or penalties		0	$ 0
Domestic Country [Member]
Income Tax Contingency [Line Items]
Operating loss carryforwards		0
State And Local Jurisdiction [Member]
Income Tax Contingency [Line Items]
Operating loss carryforwards		$ 0
Minimum [Member] | Domestic Country [Member]
Income Tax Contingency [Line Items]
Federal income tax years currently open for audits		2016
Minimum [Member] | State And Local Jurisdiction [Member]
Income Tax Contingency [Line Items]
Federal income tax years currently open for audits		2017
Maximum [Member] | Domestic Country [Member]
Income Tax Contingency [Line Items]
Federal income tax years currently open for audits		2019
Maximum [Member] | State And Local Jurisdiction [Member]
Income Tax Contingency [Line Items]
Federal income tax years currently open for audits		2019
Scenario, Plan [Member]
Income Tax Contingency [Line Items]
Federal tax rate		21.00%

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- Definition

Amount of income tax (expense) benefit for remeasurement of deferred tax liability from change in tax rate pursuant to Tax Cuts and Jobs Act of 2017.

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Tax cuts and jobs act of 2017 maximum operating loss carryforwards percentage.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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