Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
OPERATING ACTIVITIES
Net income	$ 23,298	$ 9,974
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	60,250	56,875
Stock-based compensation	3,078	2,782
Straight-line rent receivable	(5,358)	(4,816)
Straight-line rent liability	389	317
Gain on sales of real estate assets	(41,606)	(3)
Loss on extinguishment of debt	27,998
Impairments of real estate assets	3,328	6,529
Pension termination	5,260	0
Impairment of internally-developed software	654	0
Provision for bad debts, net	(182)	128
Changes in operating assets and liabilities:
Other assets	(3,784)	(14,305)
Accounts payable and accrued liabilities	(6,424)	(5,308)
Other liabilities	891	(961)
Net cash provided by operating activities	67,792	51,212
INVESTING ACTIVITIES
Acquisitions of real estate	(43,017)	(20,003)
Development of real estate	(6,027)
Acquisition of additional long-lived assets	(25,584)	(36,171)
Funding of mortgages and notes receivable		(1,244)
Proceeds from acquisition of real estate upon mortgage note receivable default		204
Proceeds from sales of real estate	94,463	5,904
Proceeds from mortgages and notes receivable repayments	9	754
Net cash provided by (used in) investing activities	19,844	(50,556)
FINANCING ACTIVITIES
Net borrowings (repayments) on unsecured credit facility	73,000	(149,000)
Borrowings on term loan		200,000
Borrowings on notes and bonds payable	249,793
Repayments on notes and bonds payable	(48,438)	(2,928)
Redemption of notes and bonds payable	(333,222)
Dividends paid	(59,954)	(57,660)
Net proceeds from issuance of common stock	40,366	27,873
Common stock redemptions	(271)	(382)
Settlement of swaps	(1,684)
Distributions to noncontrolling interest holders		(344)
Purchase of noncontrolling interest		(8,189)
Debt issuance and assumption costs	(2,314)	(1,174)
Net cash (used in) provided by financing activities	(82,724)	8,196
Increase in cash and cash equivalents	4,912	8,852
Cash and cash equivalents, beginning of period	3,519	8,671
Cash and cash equivalents, end of period	8,431	17,523
Supplemental Cash Flow Information:
Interest paid	40,533	33,904
Invoices accrued for construction, tenant improvement and other capitalized costs	4,960	$ 12,648
Mortgage notes payable assumed upon acquisition (adjusted to fair value)	9,721
Capitalized interest	$ 33