CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Data center revenue:
Rental revenue	$ 47,135	$ 38,315	$ 133,282	$ 110,152
Power revenue	23,716	18,687	65,177	51,264
Interconnection revenue	11,400	9,169	32,210	25,819
Tenant reimbursement and other	2,357	2,328	6,049	6,711
Office, light-industrial and other revenue	1,947	2,016	6,050	5,982
Total operating revenues	86,555	70,515	242,768	199,928
Operating expenses:
Property operating and maintenance	24,376	20,043	66,360	54,866
Real estate taxes and insurance	3,216	3,073	8,421	5,059
Depreciation and amortization	24,347	20,914	71,209	58,300
Sales and marketing	3,775	3,806	11,813	11,141
General and administrative	8,644	7,145	24,461	21,582
Rent	5,440	5,113	15,690	15,249
Impairment of internal-use software				1,959
Transaction costs	6	49	51	62
Total operating expenses	69,804	60,143	198,005	168,218
Operating income	16,751	10,372	44,763	31,710
Gain on real estate disposal			36
Interest income	1	1	5	5
Interest expense	(2,188)	(1,361)	(5,183)	(3,949)
Income before income taxes	14,564	9,012	39,621	27,766
Income tax benefit (expense)	(34)	(22)	(149)	(20)
Net income	14,530	8,990	39,472	27,746
Net income attributable to noncontrolling interests	5,526	3,759	16,193	11,730
Net income attributable to CoreSite Realty Corporation	9,004	5,231	23,279	16,016
Preferred stock dividends	(2,084)	(2,084)	(6,253)	(6,253)
Net income attributable to common shares	$ 6,920	$ 3,147	$ 17,026	$ 9,763
Net income per share attributable to common shares:
Basic (in dollars per share)	$ 0.26	$ 0.15	$ 0.71	$ 0.46
Diluted (in dollars per share)	$ 0.26	$ 0.14	$ 0.69	$ 0.45
Weighted average common shares outstanding
Basic (in shares)	26,126,332	21,214,825	24,029,106	21,113,700
Diluted (in shares)	26,549,537	21,708,759	24,544,612	21,679,931