Real Estate Facilities (Condensed Results Of Operations For The Property Disposition) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Real Estate Facilities
Rental income	$ 425	$ 446	$ 859	$ 1,021
Cost of operations	(219)	(244)	(412)	(526)
Depreciation	(35)	(106)	(140)	(218)
Income from discontinued operations	$ 171	$ 96	$ 307	$ 277

Depreciation attributable to real estate facilities disposed of or held for sale.

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Data Type:	xbrli:monetaryItemType
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- Definition

Cost of operations attributable to real estate facilities disposed of or held for sale.

+ Details

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Namespace Prefix:	psb
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Rental income attributable to real estate facilities disposed of or held for sale.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

After tax income (loss) from operations of a business component (exclusive of any gain or loss on disposal, or provision therefore) during the reporting period, until its disposal.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 43

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 144
-Paragraph 47
-Subparagraph c

+ Details

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- Details

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