Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Credit Risk Valuation Adjustment, Derivative Assets	$ 0		$ 0
Derivative Credit Risk Valuation Adjustment, Derivative Liabilities	$ 0		$ 0
Fair Value Inputs, Prepayment Rate	1.00%		1.00%
Annual prepayments maturity	100.00%		100.00%
Additional basis points	1.50%		1.50%
Maximum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collateral discount	30.00%	30.00%
Minimum [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Collateral discount	20.00%	20.00%

Additional basis points, annual defaults from banks.

No definition available.

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- Definition

Annual prepayments maturity, percentage.

+ References

No definition available.

+ Details

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- Definition

Unobservable Inputs Fair Value Measurement Collateral Discount Percent

+ References

No definition available.

+ Details

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- Definition

Amount of credit risk valuation adjustment to derivative assets to properly reflect the credit quality of the counterparties.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of credit risk valuation adjustment to derivative liabilities to properly reflect the credit quality of the entity.

+ 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

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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