Acquisitions and Dispositions (Details 2) (USD $)	6 Months Ended
	Jun. 30, 2012 sqft Property		Jun. 30, 2011
Asset Dispositions
Proceeds from Sale of Property Held-for-sale	$ 36,109,000		$ 3,775,000
Total dispositions and repayments Net Proceeds	90,200,000
Total dispositions and repayments Net Real Estate Investment	81,000,000
Total dispositions and repayments Other (including receivables)	(1,700,000)
Total dispositions and repayments Mortgage Note Receivable	7,800,000
Total dispositions and repayments Gain/Impairment	3,100,000
Total dispositions and repayments Square Footage	590,686
Number of Medical Office Disposed	5
Straight-line Rent Receivable	3,445,000		2,395,000
Florida [Member]
Asset Dispositions
Number of Medical Office Disposed	5
Tennessee [Member]
Asset Dispositions
Number of Medical Office Disposed	1
Real Estate Dispositions [Member]
Asset Dispositions
Proceeds from Sale of Property Held-for-sale	36,000,000
Net Real Estate Investment	42,800,000
Other (including Receivables)	1,700,000
Mortgage Note Receivable	(11,300,000)
Gain/(Impairment)	2,800,000
Square Footage, whole units	477,084
Real Estate Dispositions [Member] | Texas [Member] | Medical Office Buidlings Disposed January 2012 [Member]
Asset Dispositions
Date Disposed	Jan. 10, 2012	[1]
Proceeds from Sale of Property Held-for-sale	400,000	[1]
Net Real Estate Investment	2,500,000	[1]
Other (including Receivables)	0	[1]
Mortgage Note Receivable	(3,000,000)	[1]
Gain/(Impairment)	900,000	[1]
Square Footage, whole units	33,726	[1]
Total Consideration	3,400,000
Real Estate Dispositions [Member] | Texas [Member] | Medical Office Buidlings Disposed January 2012 [Member] | Medical Office Building One [Member]
Asset Dispositions
Area of Medical Office Building	14,748
Real Estate Dispositions [Member] | Texas [Member] | Medical Office Buidlings Disposed January 2012 [Member] | Medical Office Building Two [Member]
Asset Dispositions
Area of Medical Office Building	18,978
Real Estate Dispositions [Member] | Texas [Member] | Medical Office Buildings Disposed March 2012 [Member]
Asset Dispositions
Date Disposed	Mar. 16, 2012	[1]
Proceeds from Sale of Property Held-for-sale	0	[1]
Net Real Estate Investment	4,800,000	[1]
Other (including Receivables)	100,000	[1]
Mortgage Note Receivable	(4,500,000)	[1]
Gain/(Impairment)	(400,000)	[1]
Square Footage, whole units	82,664	[1]
Business Acquisition, Cost of Acquired Entity, Purchase Price	4,700,000
Real Estate Dispositions [Member] | Florida [Member] | Medical Office Buidlings Disposed January 2012 [Member]
Asset Dispositions
Date Disposed	Jan. 19, 2012	[1]
Proceeds from Sale of Property Held-for-sale	5,700,000	[1]
Net Real Estate Investment	3,000,000	[1]
Other (including Receivables)	200,000	[1]
Mortgage Note Receivable	0	[1]
Gain/(Impairment)	2,500,000	[1]
Square Footage, whole units	35,752	[1]
Lease Termination Fees	1,500,000
Real Estate Dispositions [Member] | Florida [Member] | Medical Office Buildings Disposed March 2012 [Member]
Asset Dispositions
Date Disposed	Mar. 02, 2012	[1]
Proceeds from Sale of Property Held-for-sale	500,000	[1]
Net Real Estate Investment	500,000	[1]
Other (including Receivables)	0	[1]
Mortgage Note Receivable	0	[1]
Gain/(Impairment)	0	[1]
Square Footage, whole units	33,895	[1]
Real Estate Dispositions [Member] | Florida [Member] | Medical Office Buidlings Disposed April 2012 [Member]
Asset Dispositions
Date Disposed	Apr. 18, 2012
Proceeds from Sale of Property Held-for-sale	28,600,000
Net Real Estate Investment	31,200,000
Other (including Receivables)	1,400,000
Mortgage Note Receivable	(3,800,000)
Gain/(Impairment)	(200,000)
Square Footage, whole units	272,571
Total Consideration	32,400,000
Number of Medical Office Disposed	5
Business Acquisition, Cost of Acquired Entity, Purchase Price	33,300,000
Net Real Estate Investment including Straight-line Rent Receviable	31,800,000
Straight-line Rent Receivable	600,000
Seller Financed Mortgage Notes Receivable	3,800,000
Business Acquisition Purchase Price Allocation Contingent Liability	600,000
Real Estate Dispositions [Member] | Tennessee [Member] | Medical Office Buidlings Disposed April 2012 [Member]
Asset Dispositions
Date Disposed	Apr. 13, 2012	[1]
Proceeds from Sale of Property Held-for-sale	800,000	[1]
Net Real Estate Investment	800,000	[1]
Other (including Receivables)	0	[1]
Mortgage Note Receivable	0	[1]
Gain/(Impairment)	0	[1]
Square Footage, whole units	18,476	[1]
Mortgage Note Repayments [Member]
Asset Dispositions
Total dispositions and repayments Net Proceeds	19,100,000
Total dispositions and repayments Net Real Estate Investment	0
Total dispositions and repayments Other (including receivables)	0
Total dispositions and repayments Mortgage Note Receivable	19,100,000
Total dispositions and repayments Gain/Impairment	0
Total dispositions and repayments Square Footage	0
Number of Mortgage Notes Receivables Repaid	2
Mortgage Note Repayments 1 and 2 [Member] [Member]
Asset Dispositions
Total dispositions and repayments Net Proceeds	4,700,000
Mortgage Note Repayment 1 [Member]
Asset Dispositions
Total dispositions and repayments Mortgage Note Receivable	1,500,000
Mortgage Note Repayment 2 [Member]
Asset Dispositions
Total dispositions and repayments Mortgage Note Receivable	3,200,000
Mortgage Note Repayment 3 [Member]
Asset Dispositions
Total dispositions and repayments Mortgage Note Receivable	4,500,000
Deconsolidation of VIE [Member]
Asset Dispositions
Total dispositions and repayments Net Proceeds	35,100,000	[2]
Total dispositions and repayments Net Real Estate Investment	38,200,000	[2]
Total dispositions and repayments Other (including receivables)	(3,400,000)	[2]
Total dispositions and repayments Mortgage Note Receivable	0	[2]
Total dispositions and repayments Gain/Impairment	300,000	[2]
Total dispositions and repayments Square Footage	113,602	[2]
Repayments of Construction Loans Payable	$ 35,100,000

[1] Previously included in assets held for sale.

[2] “Other” includes construction liabilities transferred upon deconsolidation. “Gain” includes $0.4 million of net mortgage interest income recognized, partially offset by $0.1 million of general and administrative overhead expense that had been capitalized into the project that was reversed upon deconsolidation.