Fair Value Measurements (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Goodwill, Impairment Loss	$ 0	$ 0
Fair Value Inputs, Prepayment Rate	1.00%	1.00%
Annual prepayments maturity	100.00%	100.00%
Additional basis points	150.00%	150.00%
Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collateral discount	20.00%	20.00%
Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collateral discount	30.00%	30.00%
Other Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Write Downs Included In Other Noninterest Expense	$ 444,000	$ 1,449,000

Additional basis points, annual defaults from banks.

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- Definition

Annual prepayments maturity, percentage.

+ References

No definition available.

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- Definition

Unobservable Inputs Fair Value Measurement Collateral Discount Percent

+ References

No definition available.

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- Definition

Write Downs Included In Other Noninterest Expense

+ 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

Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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