Represents the sales price of dispositions during the reporting period.

No definition available.

Name:	krc_DispositionsSalesPrice
Namespace Prefix:	krc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Net rentable area for properties owned.

+ References

No definition available.

+ Details

Name:	us-gaap_NetRentableArea
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfRealEstateProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=krc_A1800OwensStreetSanFranciscoCAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Dispositions and Real Estate Held for Sale - Operating Property Dispositions (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Mar. 31, 2021 USD ($) ft² building	Sep. 30, 2021 USD ($) building	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) building	Sep. 30, 2020 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of depreciable operating property		$ 0	$ 0	$ 457,831	$ 0
Operating Properties [Member] \| 1800 Owens Street, San Francisco, CA [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of properties \| building	1	1		1
Rentable square feet \| ft²	750,370
Sales price	$ 1,080,000