SCHEDULE III SCHEDULE III (Details2) (USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Balance at beginning of year	$ 1,768,032,000	[1]	$ 1,662,593,000	[1]	$ 1,521,177,000
Purchases of real estate properties	65,387,000		48,934,000		80,624,000
Development of real estate properties	76,240,000		55,404,000		42,148,000
Improvements to real estate properties	21,438,000		18,164,000		18,686,000
Carrying amount of investments sold	(3,475,000)		(16,756,000)		0
Write-off of improvements	(296,000)		(307,000)		(42,000)
Balance at end of year	1,927,326,000	[1],[2],[3]	1,768,032,000	[1]	1,662,593,000	[1]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Balance at beginning of year	496,247,000		451,805,000		403,187,000
Depreciation expense	54,284,000		51,564,000		48,648,000
Accumulated depreciation on assets sold	(126,000)		(6,819,000)		0
Other	(292,000)		(303,000)		(30,000)
Balance at end of year	550,113,000	[2],[3]	496,247,000		451,805,000
Estimated aggregate cost of real estate properties for federal income tax purposes	1,893,741,000
Estimated accumulated tax depreciation	356,567,000
Percentage of Occupation When Development Cost Ceased Being Capitalized	80.00%
Length of Time After Project Completion When Development Cost Ceased Being Capitalized	1 year
Secured debt	499,793,000		607,766,000
Recourse liability	5,000,000
Castilian Research Center [Member]
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Noncontrolling Interests (in hundreths)	20.00%
Noncontrolling Interests	1,794,000		1,794,000
University Business Center [Member]
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward]
Noncontrolling Interests (in hundreths)	20.00%
Noncontrolling Interests	6,496,000		6,418,000
Buildings [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Estimated useful life (in years)	40 years
Minimum [Member] | Improvements and Personal Property [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Estimated useful life (in years)	3 years
Maximum [Member] | Improvements and Personal Property [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Estimated useful life (in years)	15 years
Dominguez, Industry I and III, Kingsview, Shaw, Walnut and Washington [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	59,087,000	[4]	61,052,000	[4]
Arion 16, Broadway VI, Chino, East University I and II, Northpark I-IV, Santan 10 II, 55th Avenue and World Houston 1 and 2, 21 and 23 [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	57,368,000		60,310,000
America Plaza, Central Green, Glenmont I & II, Interstate I, II & III, Rojas, Stemmons Circle, Venture, West Loop I & II and World Houston 3-9 [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	59,827,000		61,970,000
Arion 18, Beltway VI & VII, Commerce Park II & III, Concord Dist Ctr, Interstate Dist Ctr V, VI & VII, Lakeview Business Ctr, Ridge Creek Distribution Ctr II, Southridge IV & V and World Houston 32 [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	50,519,000		52,369,000
Thirty Fifth Avenue, Beltway I, Broadway V, Lockwood, Northwest Point, Sunbelt, Techway Southwest I and World Houston 10, 11 and 14 [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	0		34,474,000
Americas Ten I, Kirby, Palm River North I, II and III, Shady Trail, Westlake I and II and World Houston 17 [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	26,907,000		27,467,000
Country Club I, Lake Pointe, Techway Southwest II and World Houston 19 and 20 [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	27,812,000		29,465,000
Huntwood and Wiegman Distribution Centers [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	28,833,000		30,332,000
Alamo Downs, Arion 1-15 and 17, Rampart I, II, III & IV, Santan 10 and World Houston 16 [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	60,131,000		63,132,000
Beltway II, III and IV, Commerce Park 1, Eastlake, Fairgrounds I-IV, Nations Ford I-IV, Techway Southwest III, Wetmore I-IV and World Houston 15 and 22 [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	61,402,000		64,374,000
Airport Commerce Center I and II, Interchange Park, Ridge Creek Distribution Center I, Southridge XII, Waterford Distribution Center and World Houston 24, 25 and 27 [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	0		52,086,000
Fortieth Avenue, Beltway V, Centennial Park, Executive Airport, Ocean View, Techway Southwest IV, Wetmore V-VIII and World Houston 26, 28, 29 and 30 [Member]
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward]
Secured debt	$ 66,805,000		$ 69,376,000

[1] Includes 20% noncontrolling interests in Castilian Research Center of $1,794,000 at December 31, 2013 and $1,794,000 at December 31, 2012 and in University Business Center of $6,496,000 and $6,418,000, respectively.

[2] Changes in Real Estate Properties follow: Years Ended December 31,2013 2012 2011(In thousands)Balance at beginning of year $1,768,032 1,662,593 1,521,177Purchases of real estate properties 65,387 48,934 80,624Development of real estate properties76,240 55,404 42,148Improvements to real estate properties21,438 18,164 18,686Carrying amount of investments sold (3,475) (16,756) —Write-off of improvements (296) (307) (42)Balance at end of year (1) $1,927,326 1,768,032 1,662,593(1)Includes 20% noncontrolling interests in Castilian Research Center of $1,794,000 at December 31, 2013 and $1,794,000 at December 31, 2012 and in University Business Center of $6,496,000 and $6,418,000, respectively.Changes in the accumulated depreciation on real estate properties follow: Years Ended December 31,2013 2012 2011(In thousands)Balance at beginning of year $496,247 451,805 403,187Depreciation expense 54,284 51,564 48,648Accumulated depreciation on assets sold (126) (6,819) —Other (292) (303) (30)Balance at end of year $550,113 496,247 451,805

[3] The estimated aggregate cost of real estate properties at December 31, 2013 for federal income tax purposes was approximately $1,893,741,000 before estimated accumulated tax depreciation of $356,567,000. The federal income tax return for the year ended December 31, 2013, has not been filed and accordingly, this estimate is based on preliminary data.

[4] This mortgage loan has a recourse liability of $5.0 million which will be released based on the secured properties generating certain base rent amounts.