Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Mar. 31, 2011	Jun. 30, 2010	Mar. 31, 2010	Jun. 30, 2011	Jun. 30, 2010
Business Segments.
Number of business segments					2
Calculation of FFO
Net income (loss)	$ 10,381	$ 24,767	$ 5,954	$ 5,562	$ 35,148	$ 11,516
Gain on sale of property	(2,346)	(19,593)			(21,939)
Equity in income of non-consolidated REITs	(1,166)	(1,772)	(380)	(253)	(2,938)	(633)
Distributions from non-consolidated REITs	1,215	1,767	1,324	1,407	2,982	2,731
Acquisition costs	9	269	129		278	129
Depreciation and amortization	12,047	10,812	9,675	9,934	22,859	19,609
Funds from operations	20,140	16,250	16,702	16,650	36,390	33,352
Real Estate Operations
Calculation of FFO
Net income (loss)	7,107	24,607	5,691	6,041	31,714	11,732
Gain on sale of property	(2,346)	(19,593)			(21,939)
Equity in income of non-consolidated REITs	(1,166)	(1,772)	(380)	(253)	(2,938)	(633)
Distributions from non-consolidated REITs	1,215	1,767	1,324	1,407	2,982	2,731
Acquisition costs	9	269	129		278	129
Depreciation and amortization	12,010	10,774	9,636	9,901	22,784	19,537
Funds from operations	16,829	16,052	16,400	17,096	32,881	33,496
Investment Banking/Investment Services
Calculation of FFO
Net income (loss)	3,274	160	263	(479)	3,434	(216)
Depreciation and amortization	37	38	39	33	75	72
Funds from operations	$ 3,311	$ 198	$ 302	$ (446)	$ 3,509	$ (144)

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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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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