Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Deferred income tax - unrealized gains (losses) on available for sale securities		$ (2,379)	$ 321
Deferred income tax - pension adjustments		(5)	668
Change in net deffered tax asset			159
Pre-1988 tax bad debt reserve		6,869	$ 6,869
State income tax rate effective (as a percent)			3.00%
Increase decrease in deferred income tax expense		1,814	$ 8,485
Reduce the corporate tax rate			21.00%
Prior maximum effective rate			35.00%
Tax benefit	$ 1,300	$ 24,189	$ 21,767	$ 14,624

Change in net deffered tax asset.

No definition available.

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- Definition

Deferred tax expense (benefit) related to pension adjustments.

+ References

No definition available.

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- Definition

Deferred tax expense (benefit) related to unrealized gains and losses on available for sale securities.

+ References

No definition available.

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- Definition

The amount of pre-1988 tax bad debt reserve base years amounts included in retained earnings.

+ References

No definition available.

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- Definition

The percentage of state income tax rate effective from next fiscal year.

+ References

No definition available.

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- Definition

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

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- Definition

Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to revisions of previously reported income tax expense.

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

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The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa.

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