CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 80,865	$ 73,483
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	105,598	96,622
Amortization of above/below market leases	(494)	(428)
Amortization of deferred financing costs	1,756	1,231
Share-based compensation	8,864	6,545
Bad debt expense	(300)	1,003
Changes in operating assets and liabilities:
Accounts receivable	5,001	(3,867)
Deferred rent receivable	(2,930)	(3,161)
Deferred leasing costs	(9,140)	(9,956)
Other assets	(5,342)	(10,385)
Accounts payable and accrued expenses	6,274	3,758
Unearned revenue, prepaid rent and other liabilities	(1,201)	(5,841)
Operating leases	(215)	1,980
Net cash provided by operating activities	188,736	150,984
CASH FLOWS FROM INVESTING ACTIVITIES
Tenant improvements	(4,191)	(6,281)
Real estate improvements	(160,269)	(108,548)
Acquisition of land	(4,383)	(12,158)
Acquisition of U.S. Colo, net of cash received	(6,298)
Net cash used in investing activities	(175,141)	(126,987)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from exercise of stock options	219	4,820
Proceeds from revolving credit facility	184,036	107,000
Payments on revolving credit facility	(199,036)	(282,000)
Proceeds from unsecured debt	150,000	275,000
Payments of loan fees and costs	(4,986)	(2,410)
Dividends and distributions	(143,769)	(126,154)
Net cash used in financing activities	(13,536)	(23,744)
Net change in cash and cash equivalents	59	253
Cash and cash equivalents, beginning of period	5,247	4,429
Cash and cash equivalents, end of period	5,306	4,682
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid for interest, net of capitalized amounts	21,209	12,310
Cash paid for operating lease liabilities	18,116	15,441
NON-CASH INVESTING AND FINANCING ACTIVITY
Construction costs payable capitalized to real estate	37,816	17,303
Accrual of dividends and distributions	51,840	46,523
NON-CASH OPERATING ACTIVITY
Lease liabilities arising from obtaining right-of-use assets	$ 114,989	$ 8,330