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Available for sale securities current par amount.

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Available for sale securities original par amount.

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Percentage of recovery estimate depository institutions.

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Percentage of recovery estimate insurance companies.

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Percentage Of Total Investment Portfolio In Unrealized Loss Position Fair Value

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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Investment Securities (Narrative) (Details) - USD ($)	3 Months Ended
Investment Securities (Narrative) (Details) - USD ($)	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2011
Investment [Line Items]
Fair value of investments reported at less than historical cost	$ 206,010,000		$ 142,932,000
Percentage of Bank portfolio	58.20%		51.50%
Proceeds from sales of securities, available for sale	$ 36,811,000	$ 5,681,000
Gross realized gain on sale of securities	154,000	129,000
Gross realized losses on sale of securities	$ 0	0
Percentage of recovery estimate depository institutions	10.00%
Percentage of recovery estimate insurance companies	15.00%
Other than temporary impairment losses investments available for sale securities	$ 0	$ 0
Pooled Trust Preferred Securities [Member]
Investment [Line Items]
Current par balance	3,900,000
Original Par	$ 4,000,000			$ 4,000,000