The total amount of cash and securities held by third party trustees pursuant to terms of debt instruments or other agreements as of the date of each statement of financial position presented, which can be used by the trustee only to pay the noncurrent portion of specified obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(b))
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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No definition available.

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Commitments, Contingent Liabilities and Off-Balance Sheet Risk (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Loss Contingencies [Line Items]
Commitments and Contingencies
Line of credit facility maximum borrowing capacity	$ 303,200
Assets Held-in-trust	191,500
Variable Rate [Member]
Loss Contingencies [Line Items]
Commitments and Contingencies		$ 94,600
Fixed Rate [Member]
Loss Contingencies [Line Items]
Commitments and Contingencies		7,100
Stand-by Letters of Credit [Member]
Loss Contingencies [Line Items]
Commitments and Contingencies	3,200	2,200
Unfunded Loan And Lines Of Credit Commitments [Member]
Loss Contingencies [Line Items]
Commitments and Contingencies	116,400	101,700
Unfunded Loan And Lines Of Credit Commitments [Member] \| Variable Rate [Member]
Loss Contingencies [Line Items]
Commitments and Contingencies	103,300
Unfunded Loan And Lines Of Credit Commitments [Member] \| Fixed Rate [Member]
Loss Contingencies [Line Items]
Commitments and Contingencies	13,100
Reserve for Unfunded Loan Commitments [Member]
Loss Contingencies [Line Items]
Commitments and Contingencies	$ 188	$ 166