Discontinued Operations (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012 Integer		Mar. 31, 2011 Integer
Discontinued Operations [Abstract]
Properties Impaired (in properties)	0		2
Properties sold (in properties)			2
Number of investment properties classified as held for sale, and properties previously sold, reported as discontinued operations (in properties)	12
Gain on sales of investment properties	$ 611		$ 129
Rental revenue	200		670
Other revenue	11		21
Depreciation and amortization	(52)		(245)
Property expenses	(48)		(209)
Provisions for impairment	0		(200)
Crest's income from discontinued operations	129		222
Income from discontinued operations	$ 851		$ 388
Per common share, basic and diluted (in dollars per share)	$ 0.01	[1]	$ 0.00	[1]

[1] The per share amounts for income from discontinued operations above and the income from continuing operations and net income reported on the consolidated statements of income have each been calculated independently.