Loans And Allowance For Loan Losses Troubled Debt Restructurings by Type of Modification (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Troubled Debt Restructuring by Type of Modification [Abstract]
Change in troubled debt restructured non-market interest rate loan balance	$ 54,100
Large business loan renewed in current year at non-market rate	31,900
Financing Receivable, Modifications [Line Items]
Restructured loans	110,608	$ 59,074
TDR Non-market interest rates [Member]
Financing Receivable, Modifications [Line Items]
Restructured loans	88,588	34,531
TDR Assistance programs [Member]
Financing Receivable, Modifications [Line Items]
Restructured loans	6,685	7,478
TDR-Bankruptcy non-affirmation [Member]
Financing Receivable, Modifications [Line Items]
Restructured loans	7,283	7,937
TDR Other [Member]
Financing Receivable, Modifications [Line Items]
Restructured loans	256	303
TDR Non-accrual loans [Member]
Financing Receivable, Modifications [Line Items]
Restructured loans	$ 7,796	$ 8,825

Change in performing troubled debt restructured loans renewed at non-market interest rates loan balance.

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- Definition

Large business loan renewed in current year at non-market rate. This loan is a large portion of the increase in performing restructured loans in the current year.

+ References

No definition available.

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- Definition

Troubled Debt Restructuring by Type of Modification [Abstract]

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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