Pro Forma Results of the Operating Partnership (Details) (USD $)	1 Months Ended	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Pro Forma Results of the Operating Partnership (Textuals) [Abstract]
Percentage of purhcase price for largest acquisition in whole purchase price	52.10%	52.10%		52.10%
Kilroy Realty, L.P. [Member]
Pro Forma Results of the Operating Partnership
Revenues		$ 95,050,000	$ 76,981,000	$ 187,478,000	$ 148,282,000
Net (loss) income available to common unitholders		(632,000)	(1,650,000)	(713,000)	3,932,000
Net (loss) income available to common unitholders per unit - basic		$ (0.02)	$ (0.04)	$ (0.02)	$ 0.07
Net (loss) income available to common unitholders per unit - diluted		$ (0.02)	$ (0.04)	$ (0.02)	$ 0.07
Actual results for certain operating data for the property
Revenues	1,425,000
Net Income	7,000
Pro Forma Results of the Operating Partnership (Textuals) [Abstract]
Percentage of purhcase price for largest acquisition in whole purchase price	52.10%	52.10%		52.10%
Acquisiton Related Expenses Excluded		$ 300,000		$ 300,000

Acquisition related expenses excluded from pro forma earnings.

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Pro Forma Results of the Operating Partnership

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The percentage of the total purchase price made up of individually significant acquired entities or acquired entites that are significant in the aggregate.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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