Debt (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Debt [Abstract]
Total debt	$ 19.7
Multifamily Housing Project Debt [Member]
Debt [Abstract]
Total debt	9.5
Land Debt [Member]
Debt [Abstract]
Total debt	200,000.0
Interest rate (in hundredths)	6.00%
Note against Remington Village [Member]
Debt [Abstract]
Amount borrowed	10.0
Balance due on the note	9.5
Amortization period of notes	20 years
Term for balloon payment	5 years
Interest rate (in hundredths)	5.50%
Senior credit facility [Member]
Debt [Abstract]
Amount borrowed	10.0
Additional amount borrowed	$ 10.0
Maturity term of senior credit facility	6 months
Interest rate (in hundredths)	2.91%

Refers to debt instrument maturity period.

No definition available.

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- Definition

Refers to the terms of notes payable to be amortized in full, measured in years.

+ References

No definition available.

+ Details

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- Definition

Represents the term for balloon payment.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Publisher FASB

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-Topic 210

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-Section S99

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Increase for additional borrowings on the credit facility during the period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

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- Definition

The effective interest rate during the reporting period.

+ References

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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+ Details

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- Definition

Including the current and noncurrent portions, the carrying value as of the balance sheet date of notes payable to banks, excluding mortgage notes, initially due beyond one year or beyond the operating cycle if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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+ Details

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