CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 45,418	$ 41,794
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of real estate assets and leasing costs	72,438	64,971
Depreciation of non-real estate furniture, fixtures and equipment	1,932	1,164
Revenue reversals (recoveries) for doubtful accounts	6,487	(3,543)
Non-cash amortization of share-based compensation awards	6,783	7,211
Non-cash amortization of deferred financing costs and debt discounts and premiums	505	135
Non-cash amortization of net below market rents	(2,586)	(2,094)
Non-cash amortization of deferred revenue related to tenant-funded tenant improvements	(4,420)	(3,817)
Straight-line rents	(19,995)	(12,895)
Amortization of right of use ground lease assets	203	144
Net change in other operating assets	7,966	(8,382)
Net change in other operating liabilities	8,209	15,102
Net cash provided by operating activities	122,940	99,790
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for development properties and undeveloped land	(167,328)	(181,695)
Expenditures for operating properties and other capital assets	(44,084)	(31,837)
Net cash used in investing activities	(211,412)	(213,532)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from issuance of common stock (Note 4)	721,794	0
Borrowings on unsecured revolving credit facility (Note 3)	190,000	190,000
Repayments on unsecured revolving credit facility (Note 3)	(55,000)	(50,000)
Principal payments and repayments of secured debt (Note 3)	(1,266)	(74,930)
Financing costs	(160)	(942)
Repurchase of common stock and restricted stock units	(9,799)	(12,130)
Distributions to noncontrolling interests in consolidated property partnerships	(2,608)	(6,301)
Dividends and distributions paid to common stockholders and common unitholders	(52,399)	(46,996)
Net cash provided by (used in) financing activities	790,562	(1,299)
Net increase (decrease) in cash and cash equivalents and restricted cash	702,090	(115,041)
Cash and cash equivalents and restricted cash, beginning of period	76,344	171,034
Cash and cash equivalents and restricted cash, end of period	778,434	55,993
Kilroy Realty L.P. [Member]
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	45,418	41,794
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of real estate assets and leasing costs	72,438	64,971
Depreciation of non-real estate furniture, fixtures and equipment	1,932	1,164
Revenue reversals (recoveries) for doubtful accounts	6,487	(3,543)
Non-cash amortization of share-based compensation awards	6,783	7,211
Non-cash amortization of deferred financing costs and debt discounts and premiums	505	135
Non-cash amortization of net below market rents	(2,586)	(2,094)
Non-cash amortization of deferred revenue related to tenant-funded tenant improvements	(4,420)	(3,817)
Straight-line rents	(19,995)	(12,895)
Amortization of right of use ground lease assets	203	144
Net change in other operating assets	7,966	(8,382)
Net change in other operating liabilities	8,209	15,102
Net cash provided by operating activities	122,940	99,790
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for development properties and undeveloped land	(167,328)	(181,695)
Expenditures for operating properties and other capital assets	(44,084)	(31,837)
Net cash used in investing activities	(211,412)	(213,532)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from issuance of common stock (Note 4)	721,794	0
Borrowings on unsecured revolving credit facility (Note 3)	190,000	190,000
Repayments on unsecured revolving credit facility (Note 3)	(55,000)	(50,000)
Principal payments and repayments of secured debt (Note 3)	(1,266)	(74,930)
Financing costs	(160)	(942)
Repurchase of common stock and restricted stock units	(9,799)	(12,130)
Distributions to noncontrolling interests in consolidated property partnerships	(2,608)	(6,301)
Dividends and distributions paid to common stockholders and common unitholders	(52,399)	(46,996)
Net cash provided by (used in) financing activities	790,562	(1,299)
Net increase (decrease) in cash and cash equivalents and restricted cash	702,090	(115,041)
Cash and cash equivalents and restricted cash, beginning of period	76,344	171,034
Cash and cash equivalents and restricted cash, end of period	$ 778,434	$ 55,993