Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
OPERATING ACTIVITIES
Net income	$ 46,908	$ 57,070
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	79,703	69,274
Other amortization	1,344	2,230
Share-based compensation	5,415	5,067
Amortization of straight-line rent receivable	(2,797)	(3,534)
Amortization of straight-line rent liability	766	316
Gain on sales of real estate assets	(29,590)	(39,532)
Impairment of real estate assets		328
Equity in losses from unconsolidated joint ventures	2
Distributions from unconsolidated joint ventures	99
Provision for bad debts, net	104	171
Changes in operating assets and liabilities:
Other assets	(778)	536
Accounts payable and accrued liabilities	(4,227)	(10,236)
Other liabilities	279	2,281
Net cash provided by operating activities	97,228	83,971
INVESTING ACTIVITIES
Acquisitions of real estate	(62,977)	(53,536)
Development of real estate	(16,377)	(10,098)
Additional long-lived assets	(37,592)	(36,329)
Proceeds from sales of real estate	55,001	117,010
Proceeds from notes receivable repayments	8	10
Net cash provided by (used in) investing activities	(61,937)	17,057
FINANCING ACTIVITIES
Net borrowings (repayments) on unsecured credit facility	46,000	(72,000)
Repayments on notes and bonds payable	(2,556)	(2,249)
Dividends paid	(75,125)	(69,898)
Net proceeds from issuance of common stock	347	1,005
Common stock redemptions	(2,633)	(1,125)
Debt issuance and assumption costs	(125)	(84)
Net cash used in financing activities	(34,092)	(144,351)
Increase (decrease) in cash, cash equivalents and restricted cash	1,199	(43,323)
Cash, cash equivalents and restricted cash at beginning of period	6,215	54,507
Cash, cash equivalents and restricted cash at beginning of period	7,414	11,184
Supplemental Cash Flow Information:
Interest paid	18,706	27,570
Invoices accrued for construction, tenant improvements and other capitalized costs	9,877	6,355
Mortgage notes payable assumed upon acquisition (adjusted to fair value)	7,995	12,460
Capitalized interest	$ 471	$ 484