Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

+ 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 02
-Paragraph 19, 20, 22
-Article 5

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Reference 1: 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(a))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 942
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Fair Value of Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Feb. 29, 2016	Dec. 31, 2015
Fair Value of Financial Instruments
Mortgage notes payable, net	$ 29,053		$ 136,299
Senior Notes	$ 346,095		$ 345,809
3.75% Senior unsecured note due In 2019
Fair Value of Financial Instruments
Interest rate (as a percent)	3.75%		3.75%
5.55% Mortgage notes due in 2016
Fair Value of Financial Instruments
Interest rate (as a percent)	5.55%		5.55%
6.21% Mortgage notes due in 2016
Fair Value of Financial Instruments
Interest rate (as a percent)	6.21%	6.21%	6.21%
5.88% Mortgage notes due in 2021
Fair Value of Financial Instruments
Interest rate (as a percent)	5.88%		5.88%
7% Mortgage notes due in 2019
Fair Value of Financial Instruments
Interest rate (as a percent)	7.00%		7.00%
8.15% Mortgage notes due in 2021
Fair Value of Financial Instruments
Interest rate (as a percent)	8.15%		8.15%
Carrying Amount
Fair Value of Financial Instruments
Mortgage notes payable, net	$ 375,148		$ 482,108
Carrying Amount \| 3.75% Senior unsecured note due In 2019
Fair Value of Financial Instruments
Senior Notes	346,095		345,809
Carrying Amount \| 5.55% Mortgage notes due in 2016
Fair Value of Financial Instruments
Mortgage notes payable, net			83,375
Carrying Amount \| 6.21% Mortgage notes due in 2016
Fair Value of Financial Instruments
Mortgage notes payable, net			23,476
Carrying Amount \| 5.88% Mortgage notes due in 2021
Fair Value of Financial Instruments
Mortgage notes payable, net	13,994		14,045
Carrying Amount \| 7% Mortgage notes due in 2019
Fair Value of Financial Instruments
Mortgage notes payable, net	9,055		9,145
Carrying Amount \| 8.15% Mortgage notes due in 2021
Fair Value of Financial Instruments
Mortgage notes payable, net	6,004		6,258
Fair Value
Fair Value of Financial Instruments
Mortgage notes payable, net	389,403		490,221
Fair Value \| 3.75% Senior unsecured note due In 2019
Fair Value of Financial Instruments
Senior Notes	358,376		351,692
Fair Value \| 5.55% Mortgage notes due in 2016
Fair Value of Financial Instruments
Mortgage notes payable, net			83,457
Fair Value \| 6.21% Mortgage notes due in 2016
Fair Value of Financial Instruments
Mortgage notes payable, net			24,038
Fair Value \| 5.88% Mortgage notes due in 2021
Fair Value of Financial Instruments
Mortgage notes payable, net	14,921		14,678
Fair Value \| 7% Mortgage notes due in 2019
Fair Value of Financial Instruments
Mortgage notes payable, net	9,600		9,645
Fair Value \| 8.15% Mortgage notes due in 2021
Fair Value of Financial Instruments
Mortgage notes payable, net	$ 6,506		$ 6,711