Long term-debt maturities repayments of principal

No definition available.

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- Definition

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

+ References

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

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13537-108611

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13531-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

+ Details

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- Definition

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

+ Details

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5580258-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5579245-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

+ Details

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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

+ Details

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

+ Details

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- Details

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- Details

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Risk Management and Use of Financial Instruments (Fair Values of Derivative Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended	12 Months Ended
	Sep. 16, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Concentration Risk, Percentage		10.00%us-gaap_ConcentrationRiskPercentage1	10.00%us-gaap_ConcentrationRiskPercentage1	10.00%us-gaap_ConcentrationRiskPercentage1
Long Term Debt Maturities Repayments Of Principal		$ 2,459,463
Derivative, Gain (Loss) on Derivative, Net	(800)	(828)	0	(2,985)
Note Five [Member] \| Unsecured Debt [Member]
Derivatives, Fair Value [Line Items]
Debt Instrument, Repurchased Face Amount	114,900
Three Year Term Loan [Member] \| Unsecured Debt [Member]
Derivatives, Fair Value [Line Items]
Debt Instrument, Repurchased Face Amount	150,000
Other Assets [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| 3.300% Interest Rate Swap Maturing January 30, 2021 [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement			549
Other Assets [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| 3.090% Interest Rate Swap Maturing October 30, 2019 [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement			218
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Notional Amount		278,610	428,610
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		(3,490)	(1,421)
Other Liabilities [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| 3.623% Interest Rate Swap Maturing February 1, 2019 [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fixed Interest Rate		3.623%
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		(2,649)	(545)
Derivative Liability, Notional Amount		200,000	200,000
Other Liabilities [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| 2.703% Interest Rate Swap Maturing February 1, 2016 [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fixed Interest Rate		2.703%
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		0	(887)
Derivative Liability, Notional Amount		0	77,000
Other Liabilities [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| 2.470% Interest Rate Swap Maturing February 1, 2015 [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fixed Interest Rate		2.47%
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		0	(283)
Derivative Liability, Notional Amount		0	50,000
Other Liabilities [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| 2.513% Interest Rate Swap Maturing May 1, 2015 [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fixed Interest Rate		2.513%
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		0	(162)
Derivative Liability, Notional Amount		0	23,000
Other Liabilities [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| 2.750% Interest Rate Swap Maturing September 30, 2017 [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fixed Interest Rate		2.75%
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		(253)	(311)
Derivative Liability, Notional Amount		27,062	27,062
Other Liabilities [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| 3.300% Interest Rate Swap Maturing January 30, 2021 [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fixed Interest Rate		3.30%
Derivative Asset, Notional Amount		25,774	25,774
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		(334)
Other Liabilities [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member] \| 3.090% Interest Rate Swap Maturing October 30, 2019 [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fixed Interest Rate		3.09%
Derivative Asset, Notional Amount		25,774	25,774
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		$ (254)