Derivative Financial Instruments - Effect of Derivative Financial Instruments on Income Statement (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Not Designated as Hedging Instrument \| Interest rate contracts \| Other income
Derivative [Line Items]
Amount of Gain (Loss) Recognized Income on Derivative	$ (100)	$ 19
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Expense
Derivative [Line Items]
Amount of Gain (Loss) Reclassified from Other Comprehensive Income into Income (Effective Portion)	(354)	(344)
Designated as Hedging Instrument \| Interest rate contracts \| Cash Flow Hedging
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	$ (1,276)	$ (1,266)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (a),(c),(d),(e)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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