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Common stock cash dividend declared by an entity during the period. This element includes paid and unpaid dividends declared during the period.

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Number of shares issued during the period as a result of any share-based compensation plan other than an employee stock ownership plan (ESOP).

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Consolidated Statement Of Equity (USD $) In Thousands, except Share data	Preferred Stock [Member]	Common Stock [Member]	Paid-in Capital [Member]	Cumulative Net Income [Member]	Cumulative Distributions [Member]	Total PS Business Parks, Inc.'s Shareholders' Equity [Member]	Noncontrolling Interests [Member]	Total
Balances, value at Dec. 31, 2010	$ 598,546	$ 246	$ 557,882	$ 784,616	$ (747,762)	$ 1,193,528	$ 229,597	$ 1,423,125
Balances, shares at Dec. 31, 2010	23,942	24,671,177
Repurchase of preferred stock units, net of issuance costs, value			10,107			10,107	(49,194)	(39,087)
Exercise of stock options, value			1,050			1,050		1,050
Exercise of stock options, shares		24,600						24,600
Stock compensation, net, value			252			252		252
Stock compensation, net, shares		20,367
Net income				48,908		48,908	1,072	49,980
Distributions:
Preferred stock					(20,899)	(20,899)		(20,899)
Common stock					(21,742)	(21,742)		(21,742)
Noncontrolling interests							(6,627)	(6,627)
Adjustment to noncontrolling interests in underlying operating partnership			(9,122)			(9,122)	9,122	(9,122)
Balances, value at Jun. 30, 2011	$ 598,546	$ 246	$ 560,169	$ 833,524	$ (790,403)	$ 1,202,082	$ 183,970	$ 1,386,052
Balances, shares at Jun. 30, 2011	23,942	24,716,144