Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Sep. 30, 2011 sqft Segment Y Property D	Sep. 30, 2010
Business Segments
Number of business segments							2
Calculation of FFO
Net income (loss)	$ 3,314	$ 10,381	$ 24,767	$ 4,757	$ 5,954	$ 5,562	$ 38,462	$ 16,273
Gain on sale of property		(2,346)	(19,593)				(21,939)
Equity in income of non-consolidated REITs	(573)	(1,166)	(1,772)	(404)	(380)	(253)	(3,511)	(1,037)
Distributions from non-consolidated REITs	1,104	1,215	1,767	1,192	1,324	1,407	4,086	3,923
Acquisition costs	185	9	269	(4)	129		463	125
Depreciation and amortization	12,332	12,047	10,812	10,511	9,675	9,934	35,191	30,120
Funds from operations	16,362	20,140	16,250	16,052	16,702	16,650	52,752	49,404
Real Estate Operations
Calculation of FFO
Net income (loss)	3,453	7,107	24,607	5,158	5,691	6,041	35,167	16,890
Gain on sale of property		(2,346)	(19,593)				(21,939)
Equity in income of non-consolidated REITs	(573)	(1,166)	(1,772)	(404)	(380)	(253)	(3,511)	(1,037)
Distributions from non-consolidated REITs	1,104	1,215	1,767	1,192	1,324	1,407	4,086	3,923
Acquisition costs	185	9	269	(4)	129		463	125
Depreciation and amortization	12,294	12,010	10,774	10,445	9,636	9,901	35,078	29,982
Funds from operations	16,463	16,829	16,052	16,387	16,400	17,096	49,344	49,883
Investment Banking/Investment Services
Calculation of FFO
Net income (loss)	(139)	3,274	160	(401)	263	(479)	3,295	(617)
Depreciation and amortization	38	37	38	66	39	33	113	138
Funds from operations	$ (101)	$ 3,311	$ 198	$ (335)	$ 302	$ (446)	$ 3,408	$ (479)

Represents net income (determined in accordance with GAAP), excluding gains (or losses) from sales of property and acquisition costs of newly acquired properties that are not capitalized, plus depreciation and amortization, and after adjustments to exclude non-cash income (or losses) from non-consolidated or Sponsored REITs, plus distributions received from non-consolidated or Sponsored REITs.

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This item represents the entity's proportionate share for the period of the net income (loss) from unconsolidated Sponsored REITs to which the equity method of accounting is applied as well as consolidated net income (loss), if any, from Sponsored REITs.

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The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

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