Declining Prepayment Penalty After Three Years

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- Definition

Long term-debt maturities repayments of principal

+ References

No definition available.

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- Definition

Amount of noncash expense included in interest expense to issue debt and obtain financing associated with the related debt instruments. Alternate captions include noncash interest expense.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 5

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 8

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

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No definition available.

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- Definition

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

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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

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-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 4C

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

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- Definition

Gross amount of debt extinguished.

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No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

The effective interest rate during the reporting period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

Weighted average interest rate of long-term debt outstanding.

+ References

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Debt Obligations (Details Textuals 2) (USD $)	0 Months Ended	12 Months Ended
Debt Obligations (Details Textuals 2) (USD $)	Sep. 16, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Long Term Debt Maturities Repayments Of Principal		$ 2,459,463,000
Extinguishment of Debt, Amount		376,174,000us-gaap_ExtinguishmentOfDebtAmount	29,250,000us-gaap_ExtinguishmentOfDebtAmount	164,968,000us-gaap_ExtinguishmentOfDebtAmount
Amortization of Financing Costs		5,148,000us-gaap_AmortizationOfFinancingCosts	4,676,000us-gaap_AmortizationOfFinancingCosts	6,208,000us-gaap_AmortizationOfFinancingCosts
Derivative, Gain (Loss) on Derivative, Net	(800,000)	(828,000)	0	(2,985,000)
Unsecured Debt [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate During Period			0.29%
Long-term Debt, Gross		1,803,529,000	1,929,703,000
Unsecured Debt [Member] \| Three Year Term Loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		0	150,000,000
Unsecured Debt [Member] \| Four-Year Term Loan - Variable [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		0	100,000,000
Unsecured Debt [Member] \| Seven Year Term Loan [Member]
Debt Instrument [Line Items]
Declining prepayment penalty in year three		1.00%
Derivative, Average Fixed Interest Rate		3.623%
Long-term Debt, Gross		200,000,000	200,000,000
Unsecured Debt [Member] \| Note 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		250,000,000	250,000,000
Unsecured Debt [Member] \| Note Five [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		0	157,625,000
Extinguishment of Debt, Amount	42,700,000
Unsecured Debt [Member] \| Note Six [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		149,919,000	149,919,000
Unsecured Debt [Member] \| Letter of Credit [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.50%
Letters of Credit Outstanding, Amount		4,300,000
Unsecured Debt [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.50%
Line of Credit Facility, Remaining Borrowing Capacity		595,700,000
Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate		5.72%	5.73%	6.65%
Long-term Debt, Gross		655,934,000	669,762,000
Note Six [Member]
Debt Instrument [Line Items]
Extinguishment of Debt, Amount			$ 510,000	$ 99,571,000