Income Taxes (Narratives) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
Statutary tax rate	39.00%	39.00%	(39.00%)
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	$ 1,300	$ 2,000
Interest and Penalties Released Related to Unrecognized Tax Benefits	(775)	(135)	$ (385)
Deferred Tax Assets, Net	127,421	124,200
OtherComprehensiveIncomeLossTax	(564)	(983)
Income Tax Expense (Benefit)	15,443	25,994	(17,554)
Exempt Income	10,000	10,000	17,600
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	97	(229)
Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations	$ 877	$ 1,363	$ 0
Effective tax rate	22.66%	30.51%	(87.52%)
International Banking Entity [Member]
Exempt Income	$ 9,600	$ 10,300	$ 6,300

Interest and Penalties released related to unrecognized tax benefits due to negociation with IRS.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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

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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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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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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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities exempt from state, federal and other income tax.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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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 interest expense accrued for an underpayment of income taxes.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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