Past Due Loans, Allowance For Credit Losses, Impaired Loans, and TDRs (Details) - TDRs That Were Restructured $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($) loan	Dec. 31, 2014 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	2	3	10
Pre-Modification Recorded Investment	$ 6,205	$ 445	$ 24,619
Funds Disbursed	0	0	0
Interest and Escrow Capitalized	0	0	0
Charge-offs	1,083	0	0
Post-Modification Recorded Investment	$ 5,122	$ 445	$ 24,619
Commercial real estate loans \| Office, retail, and industrial
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1		1
Pre-Modification Recorded Investment	$ 5,460		$ 417
Funds Disbursed	0		0
Interest and Escrow Capitalized	0		0
Charge-offs	1,083		0
Post-Modification Recorded Investment	$ 4,377		$ 417
Commercial real estate loans \| Other commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1
Pre-Modification Recorded Investment	$ 745
Funds Disbursed	0
Interest and Escrow Capitalized	0
Charge-offs	0
Post-Modification Recorded Investment	$ 745
Commercial real estate loans \| Multi-family
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan			1
Pre-Modification Recorded Investment			$ 275
Funds Disbursed			0
Interest and Escrow Capitalized			0
Charge-offs			0
Post-Modification Recorded Investment			$ 275
Consumer loans \| Home equity
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan		1	1
Pre-Modification Recorded Investment		$ 120	$ 75
Funds Disbursed		0	0
Interest and Escrow Capitalized		0	0
Charge-offs		0	0
Post-Modification Recorded Investment		$ 120	$ 75
Consumer loans \| 1-4 family mortgages
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan		2
Pre-Modification Recorded Investment		$ 325
Funds Disbursed		0
Interest and Escrow Capitalized		0
Charge-offs		0
Post-Modification Recorded Investment		$ 325
Commercial, industrial, and agricultural \| Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan			7
Pre-Modification Recorded Investment			$ 23,852
Funds Disbursed			0
Interest and Escrow Capitalized			0
Charge-offs			0
Post-Modification Recorded Investment			$ 23,852

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No definition available.

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- Definition

This item represents the total amount of funds disbursed on troubled debt restructurings related to financing receivables.

+ References

No definition available.

+ Details

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- Definition

This item represents the total amount of interest and escrow capitalized on troubled debt restructurings related to financing receivables.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Number of 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 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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