The minimum interest rate on a variable rate on the debt instrument.

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- Definition

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.

+ Details

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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.

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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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Notes and Other Receivables (Details) (USD $) In Thousands, unless otherwise specified			6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2011 Notes Receivable [Member] Secured Due August 2011 [Member]	Dec. 31, 2010 Notes Receivable [Member] Secured Due August 2011 [Member]	Jun. 30, 2011 Notes Receivable [Member] Secured Due November 2011 [Member]	Dec. 31, 2010 Notes Receivable [Member] Secured Due November 2011 [Member]	Jun. 30, 2011 Notes Receivable [Member] Secured Due March 2012 [Member]	Dec. 31, 2010 Notes Receivable [Member] Secured Due March 2012 [Member]	Jun. 30, 2011 Notes Receivable [Member] Secured 1 Due December 2012 [Member]	Dec. 31, 2010 Notes Receivable [Member] Secured 1 Due December 2012 [Member]	Jun. 30, 2011 Notes Receivable [Member] Secured 2 Due December 2012 [Member]	Dec. 31, 2010 Notes Receivable [Member] Secured 2 Due December 2012 [Member]	Jun. 30, 2011 Notes Receivable [Member] Secured Due February 2014 [Member]	Dec. 31, 2010 Notes Receivable [Member] Secured Due February 2014 [Member]	Jun. 30, 2011 Other Receivables [Member]	Dec. 31, 2010 Other Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notes receivable	$ 49,956	$ 49,444	$ 3,221	$ 3,221	$ 971	$ 971	$ 7,331	$ 7,331	$ 10,928	$ 10,930	$ 6,463	$ 6,513	$ 17,261	$ 16,708	$ 3,781	$ 3,770
Stated interest rate (in hundredths)			6.50%	6.50%	8.00%	8.00%	9.80%		8.80%				6.30%	6.30%
Base reference rate used for variable rate debt (in hundredths)								LIBOR		LIBOR	LIBOR	LIBOR
Interest rate spread over the base reference rate (in hundredths)								3.80%		4.80%	8.00%	8.00%
Interest rate floor (in hundredths)								5.00%		5.00%