Accounting Policies reclassification of debt issuance (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
New Accounting Pronouncement, Early Adoption [Line Items]
Prepaid expenses and other assets	$ 109,787	$ 115,692
Notes Payable	743,181	743,149
Mortgage notes payable, net	418,052	417,194
New Accounting Pronouncement, Early Adoption, Effect [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Prepaid expenses and other assets	114,913	121,082
Debt Issuance Cost	(5,126)	(5,390)
Notes payable
New Accounting Pronouncement, Early Adoption [Line Items]
Notes Payable	743,181	743,149
Notes payable \| New Accounting Pronouncement, Early Adoption, Effect [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Notes Payable	747,638	747,208
Debt Issuance Cost	(4,457)	(4,059)
Mortgage payable
New Accounting Pronouncement, Early Adoption [Line Items]
Mortgage notes payable, net	418,052	417,194
Debt Issuance Cost	(669)	(1,331)
Mortgage payable \| New Accounting Pronouncement, Early Adoption, Effect [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Mortgage notes payable, net	418,721	418,525
Debt Issuance Cost	$ (669)	$ (1,331)

For an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28555-108399

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 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 13, 16
-Article 9

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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