Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Taxes [Abstract]
Effective tax rate	10.90%	22.00%	22.70%
Unrecognized tax benefits	$ 0	$ 0	$ 0
Tax interest and penalties expense	0	0	$ 0
Credit to income tax expense		$ 909,000
Cost of segregation study	$ 717,000

Effective Income Tax Rate Reconciliation, Cost Segregation Study Amount

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- Definition

Tax Cuts And Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of unrecognized tax benefits.

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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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