Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
REVENUES:
Rental income	$ 633,896	$ 574,413	$ 525,355
Tenant reimbursements	76,559	61,079	53,774
Other property income (Note 18)	8,546	7,080	2,146
Total revenues	719,001	642,572	581,275
EXPENSES:
Property expenses	129,971	113,932	105,378
Real estate taxes	66,449	55,206	50,223
Provision for bad debts	3,269	0	545
Ground leases (Notes 5 and 18)	6,337	3,439	3,096
General and administrative expenses	60,581	57,029	48,265
Acquisition-related expenses (Note 2)	0	1,902	497
Depreciation and amortization (Notes 2 and 5)	245,886	217,234	204,294
Total expenses	512,493	448,742	412,298
OTHER (EXPENSES) INCOME:
Interest income and other net investment gains (Note 19)	5,503	1,764	243
Interest expense (Note 9)	(66,040)	(55,803)	(57,682)
Loss on early extinguishment of debt (Note 9)	(5,312)	0	0
Total other (expenses) income	(65,849)	(54,039)	(57,439)
INCOME FROM OPERATIONS BEFORE GAINS (LOSSES) ON SALES OF REAL ESTATE	140,659	139,791	111,538
Net gain (loss) on sales of land (Note 4)	449	(295)	17,116
Gains on sales of depreciable operating properties (Note 4)	39,507	164,302	109,950
NET INCOME	180,615	303,798	238,604
Net income attributable to noncontrolling common units of the Operating Partnership (Notes 2 and 11)	(3,223)	(6,635)	(4,339)
Net income attributable to noncontrolling interests in consolidated property partnerships (Notes 2 and 11)	(12,780)	(3,375)	(184)
Total income attributable to noncontrolling interests	(16,003)	(10,010)	(4,523)
NET INCOME ATTRIBUTABLE TO KILROY REALTY CORPORATION / KILROY REALTY, L.P.	164,612	293,788	234,081
Preferred dividends (Note 13)	(5,774)	(13,250)	(13,250)
Original issuance costs of redeemed preferred stock and preferred units	(7,589)	0	0
Total preferred dividends	(13,363)	(13,250)	(13,250)
NET INCOME AVAILABLE TO COMMON STOCKHOLDERS/UNITHOLDERS	$ 151,249	$ 280,538	$ 220,831
Net income available to common stockholders per share - basic	$ 1.52	$ 3.00	$ 2.44
Net income available to common stockholders per share - diluted	$ 1.51	$ 2.97	$ 2.42
Weighted average shares of common stock outstanding – basic	98,113,561	92,342,483	89,854,096
Weighted average shares of common stock outstanding – diluted	98,727,331	93,023,034	90,395,775