Notes and Other Receivables (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2011	Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	$ 51,599	$ 49,444
Interest rate spread over the base reference rate (in hundredths)	1.25%
Notes Receivable [Member] \| Secured Due February 2014 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	17,446	16,708
Stated interest rate (in hundredths)	6.30%	6.30%
Notes Receivable [Member] \| Secured 1 Due December 2012 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	10,931	10,930
Stated interest rate (in hundredths)	8.80%	8.80%
Notes Receivable [Member] \| Secured Due March 2012 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	7,390	7,331
Stated interest rate (in hundredths)	9.80%	9.80%
Notes Receivable [Member] \| Secured 2 Due December 2012 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	6,443	6,513
Base reference rate used for variable rate debt (in hundredths)	LIBOR	LIBOR
Interest rate spread over the base reference rate (in hundredths)	8.00%	8.00%
Notes Receivable [Member] \| Secured 1 Due November 2011 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	3,199	3,221
Stated interest rate (in hundredths)	6.50%	6.50%
Notes Receivable [Member] \| Secured 2 Due November 2011 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	971	971
Stated interest rate (in hundredths)	8.00%	8.00%
Other Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	$ 5,219	$ 3,770

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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

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- Definition

The reference rate for the variable rate of the interest rate derivative, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ Details

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- Definition

The stated interest rate on the mortgage loan receivable or the weighted average interest rate on a group of loans.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 29

-Article 12

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=6882300&loc=d3e5864-122674

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- Definition

For an unclassified balance sheet, an amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-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 210.5-02.3)

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

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