Loans and Asset Quality Information (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans and Leases Receivable Disclosure [Line Items]
Loans pledged as collateral	$ 4,000,000	$ 3,800,000
Loans	4,451,525	4,247,765	$ 4,043,355
Payments that exceeded carrying amount of PCI loans	406	772	1,064
Loan discount accretion income	348	493	962
Additional loan interest income	58	279	102
Interest income on restructured loans	1,300	1,500	1,300
SBA Loans
Loans and Leases Receivable Disclosure [Line Items]
Remaining unaccreted discount	7,100	5,700
Purchased Non-Impaired Loans
Loans and Leases Receivable Disclosure [Line Items]
Remaining unaccreted discount	11,100	15,000	$ 21,500
Credit Card Loans
Loans and Leases Receivable Disclosure [Line Items]
Loans	30,900	26,500
Real estate – mortgage – residential (1-4 family) first mortgages
Loans and Leases Receivable Disclosure [Line Items]
Presold mortgages in process of settlement	600	700
Officers And Directors
Loans and Leases Receivable Disclosure [Line Items]
Due from related parties	$ 5,500	$ 5,700

Additional loan interest income.

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Discount accretion loan interest income.

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Interest and fee income, actually collected, generated by loans the Entity intends and has the ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (1) industrial and agricultural; (2) real estate; and (3) real estate construction loans; (4) trade financing; (5) lease financing; (6) home equity lines-of-credit; (7) automobile and other vehicle loans; and (8) credit card and other revolving-type loans. Also includes interest income for leases held by the Entity.

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Refers to payments that exceeded initial carrying values of purchased impaired laons.

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No definition available.

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The amount of the loan's contractually required payments receivable in excess of the amount of its cash flows expected to be collected. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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