Financial Instruments - Notional Amounts (Details) (Interest rate swaps, USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Derivatives designated as and not designated as cash flow hedges:
Notional Amount	$ 75,000invest_DerivativeNotionalAmount
Not designated as cash flow hedge
Derivatives designated as and not designated as cash flow hedges:
Notional Amount	75,000	75,000
Interest Rate Derivative Assets, at Fair Value	0	0
Interest Rate Derivative Liabilities, at Fair Value	$ 471	$ 723

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

+ Details

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

+ Details

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- Details

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