v3.25.4
Secured and Unsecured Debt of the Operating Partnership - Unsecured Revolving Credit Facility and Term Loan Facility (Details)
 12 Months Ended
Dec. 31, 2025
USD ($)
extension_option
Dec. 31, 2024
USD ($)
extension_option
Debt Instrument [Line Items]    
Deferred financing costs, net $ 9,150,000 $ 12,692,000
Number of extension options | extension_option   2
Revolving credit facility | Kilroy Realty L.P.    
Debt Instrument [Line Items]    
Outstanding borrowings 0 $ 0
Remaining borrowing capacity 1,100,000,000 1,100,000,000
Total borrowing capacity $ 1,100,000,000 $ 1,100,000,000
Interest rate 5.07% 5.69%
Annual facility fee (percent) 0.25% 0.25%
Deferred financing costs, net $ 9,150,000 $ 12,692,000
Contingent additional borrowings $ 500,000,000.0 $ 500,000,000.0
Extension period (in months) 6 months 6 months
Revolving credit facility | Kilroy Realty L.P. | Unsecured Revolving Credit Facility    
Debt Instrument [Line Items]    
Outstanding letters of credit $ 5,200,000 $ 5,200,000
Debt instrument, reduction interest rate 0.01% 0.01%
Revolving credit facility | Kilroy Realty L.P. | Unsecured Revolving Credit Facility | Secured Overnight Financing Rate (SOFR)    
Debt Instrument [Line Items]    
Basis spread on SOFR and LIBOR 1.10% 1.10%
Revolving Credit Facility and Term Loan Facility | Kilroy Realty L.P. | Unsecured Revolving Credit Facility | Adjusted SOFR    
Debt Instrument [Line Items]    
Basis spread on SOFR and LIBOR 0.10% 0.10%
Unsecured debt | Kilroy Realty L.P. | 2024 Term Loan Facility    
Debt Instrument [Line Items]    
Number of extension options | extension_option 2  
Extension period (in months) 12 months  
Line of credit | Kilroy Realty L.P. | 2024 Term Loan Facility    
Debt Instrument [Line Items]    
Outstanding borrowings $ 200,000,000 $ 200,000,000
Interest rate 5.02% 5.70%
Deferred financing costs, net $ 277,000 $ 1,229,000
Contingent additional borrowings $ 130,000,000.0  
Term Loan Facility | Kilroy Realty L.P. | 2024 Term Loan Facility | Secured Overnight Financing Rate (SOFR)    
Debt Instrument [Line Items]    
Basis spread on SOFR and LIBOR 1.20% 1.20%