Significant Acquisitions and Dispositions (Tables)

12 Months Ended

Dec. 31, 2012

Dec. 31, 2012

Other Two Thousand Twelve Acquisitions [Member] [Domain]

Dec. 31, 2011

Premier Portfolio [Member]

Dec. 31, 2011

Other 2011 Acquisitions [Member]

Dec. 31, 2010

Dugan Realty [Member]

Dec. 31, 2010

Other 2010 Acquisitions [Member]

Summary of Significant Assumptions Utilized in Estimates

The range of most significant assumptions utilized in making the lease-up and future disposition estimates used in calculating the "as-if vacant" value of each building acquired during 2012 and 2011 are as follows:

	2012		2011
	Low	High	Low	High
Discount rate	7.13%	10.78%	6.40%	11.10%
Exit capitalization rate	5.75%	8.88%	4.80%	10.00%
Lease-up period (months)	6	36	9	36
Net rental rate per square foot - Industrial	$2.75	$7.62	$2.75	$6.70
Net rental rate per square foot - Office	$—	$—	$8.61	$16.00
Net rental rate per square foot - Medical Office	$13.20	$26.14	$13.75	$27.62

Summary of Allocation of Fair Value of Amounts Recognized

The following table summarizes our allocation of the fair value of amounts recognized for each major class of asset and liability (in thousands) for these acquisitions:

Real estate assets	$	668,149
Lease-related intangible assets	111,509
Other assets	5,714
Total acquired assets	785,372
Secured debt	100,826
Other liabilities	11,928
Total assumed liabilities	112,754
Fair value of acquired net assets	$	672,618

The following table summarizes our allocation of the fair value of amounts recognized for each major class of assets and liabilities related to the 55 properties and other real estate assets from the Premier Portfolio that have been purchased through December 31, 2011 (in thousands): 

	Acquired During Year Ended December 31, 2011		Acquired During Year Ended December 31, 2010		Total
Real estate assets	$	153,656	$	249,960	$	403,616
Lease-related intangible assets	25,445		31,091		56,536
Other assets	2,571		1,801		4,372
Total acquired assets	181,672		282,852		464,524
Secured debt	125,003		158,238		283,241
Other liabilities	4,284		4,075		8,359
Total assumed liabilities	129,287		162,313		291,600
Fair value of acquired net assets	$	52,385	$	120,539	$	172,924

The following table summarizes our allocation of the fair value of amounts recognized for each major class of assets and liabilities (in thousands) for these acquisitions:

Real estate assets	$	503,556
Lease-related intangible assets	70,994
Other assets	879
Total acquired assets	575,429
Secured debt	40,072
Other liabilities	8,300
Total assumed liabilities	48,372
Fair value of acquired net assets	$	527,057

The following table summarizes our allocation of the fair value of amounts recognized for each major class of assets and liabilities (in thousands):

Real estate assets	$	502,418
Lease-related intangible assets	107,155
Other assets	28,658
Total acquired assets	638,231
Secured debt	285,376
Other liabilities	20,243
Total assumed liabilities	305,619
Fair value of acquired net assets (represents 100% interest)	$	332,612

The following table summarizes our allocation of the fair value of amounts recognized for each major class of assets and liabilities (in thousands): 

Real estate assets	$	254,014
Lease-related intangible assets	71,844
Other assets	3,652
Total acquired assets	329,510
Secured and unsecured debt	63,458
Other liabilities	5,645
Total assumed liabilities	69,103
Fair value of acquired net assets	$	260,407

Business Acquisition, Preexisting Relationship, Calculation of Gain Loss on Acquisition [Table Text Block]

Our gain on acquisition, considering the derecognition of the put liability, was calculated as follows (in thousands):

Fair value of existing interest (represents 50% interest)	$	166,306
Less:
Carrying value of investment in Dugan	158,591
Put option liability derecognized	(50,000		)
	108,591
Gain on acquisition	$	57,715