Income Taxes (Textual) [Abstract]

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Tax cuts and jobs act of 2017 change in tax rate income tax expense benefit.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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

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The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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

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Amount of unrecognized tax benefits.

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Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Income Taxes (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes (Textual) [Abstract]
Federal statutory income tax rate		21.00%	35.00%
Valuation allowance for deferred tax assets	$ 0		$ 0	$ 0
Unrecognized tax benefits	0		0	0
Penalties or interest			0	0
Amounts accrued for penalties or interest	0		0	0
Impact of enactment of federal tax reform	1,800		1,793	0	$ 0
Alternative minimum tax credit carryforward	$ 64		$ 64	$ 205
Earliest Tax Year
Income Taxes (Textual) [Abstract]
Open tax year			2014
Latest Tax Year
Income Taxes (Textual) [Abstract]
Open tax year			2017