Net Income Available to Common Unitholders Per Unit of the Operating Partnership (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Numerator:
Net income available to common unitholders	$ 79,757	$ 47,028	$ 179,990	$ 580,498
Allocation to participating securities	(287)	(388)	(980)	(1,124)
Numerator for basic and diluted net income available to common stockholders	$ 79,470	$ 46,640	$ 179,010	$ 579,374
Denominator:
Basic weighted average vested units outstanding (in shares)	116,872,953	116,456,796	116,782,621	116,418,113
Effect of dilutive securities (in shares)	369,458	505,884	380,528	476,321
Diluted weighted average vested shares and common stock equivalents outstanding (in shares)	117,242,411	116,962,680	117,163,149	116,894,434
Basic earnings per unit:
Net income available to common stockholders per unit (in dollars per share)	$ 0.68	$ 0.40	$ 1.53	$ 4.98
Diluted earnings per unit:
Net income available to common stockholders per unit (in dollars per share)	$ 0.68	$ 0.40	$ 1.53	$ 4.96
Kilroy Realty L.P.
Numerator:
Net income available to common unitholders	$ 80,421	$ 47,488	$ 181,685	$ 586,198
Allocation to participating securities	(287)	(388)	(980)	(1,124)
Numerator for basic and diluted net income available to common stockholders	$ 80,134	$ 47,100	$ 180,705	$ 585,074
Denominator:
Basic weighted average vested units outstanding (in shares)	118,023,527	117,607,370	117,933,195	117,568,687
Effect of dilutive securities (in shares)	369,458	505,884	380,528	476,321
Diluted weighted average vested shares and common stock equivalents outstanding (in shares)	118,392,985	118,113,254	118,313,723	118,045,008
Basic earnings per unit:
Net income available to common stockholders per unit (in dollars per share)	$ 0.68	$ 0.40	$ 1.53	$ 4.98
Diluted earnings per unit:
Net income available to common stockholders per unit (in dollars per share)	$ 0.68	$ 0.40	$ 1.53	$ 4.96