Fair Values of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Carrying Amount
Financial Assets:
Cash and cash equivalents	$ 66,675	$ 116,241
Mortgage loan receivable	3,395	3,417
Interest rate swap agreements	412	1,131
Financial Liabilities:
Mortgage notes payable	1,298,971	1,339,450
Notes payable to banks	593,000	481,500
Interest rate swap agreements	13,790	11,077
Fair Value
Financial Assets:
Cash and cash equivalents	66,675	116,241
Mortgage loan receivable	3,395	3,417
Interest rate swap agreements	412	1,131
Financial Liabilities:
Mortgage notes payable	1,309,047	1,327,637
Notes payable to banks	592,258	477,967
Interest rate swap agreements	$ 13,790	$ 11,077

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

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Fair value, after the 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 not elected to be offset.

+ References

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-Publisher FASB

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-SubTopic 10

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

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-Paragraph 3

-Subparagraph (c)

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-Topic 210

-SubTopic 20

-Section 55

-Paragraph 10

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value portion of contractual obligation to pay money on demand or on fixed or determinable dates.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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

-Publisher FASB

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-SubTopic 10

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Fair value portion of notes payable.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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