Discontinued Operations (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Discontinued Operations [Abstract]
Properties impaired (in properties)	1	1	4	3
Properties sold (in properties)	1	1	3	3
Number of investment properties classified as held for sale, and properties previously sold, reported as discontinued operations (in properties)	4		4
Income from discontinued operations [Abstract]
Gain on sales of investment properties	$ 3,094	$ 1,919	$ 4,319	$ 4,284
Rental revenue	83	519	439	2,209
Other revenue	7	7	35	25
Depreciation and amortization	(26)	(260)	(264)	(892)
Property expenses	(111)	(230)	(365)	(896)
Provisions for impairment	(158)	(84)	(368)	(171)
Crest's income from discontinued operations	222	268	664	717
Income from discontinued operations	$ 3,111	$ 2,139	$ 4,460	$ 5,276
Per common share, basic and diluted (in dollars per share)	$ 0.02	$ 0.02	$ 0.04	$ 0.05

Amount of depreciation and amortization expenses attributable to the discontinued operations of an entity during the reporting period

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- Definition

Amount of other revenues, not previously identified, attributable to the discontinued operation of an entity during the reporting period

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Amount of property expenses attributable to the discontinued operations of an entity during the reporting period.

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Amount of rental revenues attributable to the discontinued operation of an entity, during the reporting period.

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- Definition

Element represents income (loss) from discontinued operations of real estate acquired for resale by a subsidiary, net of income tax, as a component of income before extraordinary items and accounting changes before amount of possible allocation to noncontrolling interests. Includes (net of tax): income (loss) from operations for phase-out period, gain (loss) on disposal, provision (or any reversals of) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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- Definition

The number of investment properties classified as held for sale.

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- Definition

The number of properties impaired.

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- Definition

The number of impaired properties sold.

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- Definition

Gain (loss) after tax expense or benefit, not previously recognized and resulting from the sale of a business component, which is recognized at the date of sale. A gain (loss) reflects the amount by which the consideration received exceeds (is exceeded by) the net carrying amount (reflecting previous provisions for loss on disposal, if any) of the disposal group.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

-Section 45

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

-Paragraph 43

-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.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

-Paragraph 27, 28, 29, 30

-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.

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- Definition

This element represents the overall income (loss) from a disposal group apportioned to the parent that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items after deduction or consideration of the amount which may be allocable to noncontrolling interests, if any. Includes the following (net of tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

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-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.

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The amount of income (loss) derived from discontinued operations during the period, net of related tax effect, per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

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