Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities:
Net income	$ 37,952	$ 65,958
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	126,657	123,082
Loss on sale of depreciable real estate assets	29	13
Loss (gain) on sale of non-depreciable real estate assets	376	(8,963)
Loss on embedded derivative in preferred shares	27,638	524
Stock compensation expense	5,288	4,785
Amortization of debt issuance costs, discounts and premiums	1,157	1,747
Net change in operating accounts and other operating activities	(38,495)	(32,468)
Net cash provided by operating activities	160,602	154,678
Cash flows from investing activities:
Purchases of real estate and other assets	(5,004)	(13,595)
Capital improvements, development and other	(84,610)	(53,214)
Distributions from real estate joint ventures		43
Contributions to affiliates	(900)
Proceeds from disposition of real estate assets	525	13,882
Net cash used in investing activities	(89,989)	(52,884)
Cash flows from financing activities:
Proceeds from revolving credit facility	130,000	145,000
Repayments of revolving credit facility	(30,000)	(610,000)
Net repayments of commercial paper	(70,000)
Proceeds from notes payable		490,435
Principal payments on notes payable	(1,740)	(1,847)
Payment of deferred financing costs		(4,705)
Distributions to noncontrolling interests	(4,067)	(3,947)
Distributions paid on common shares/units	(114,270)	(109,324)
Distributions paid on preferred shares/units	(922)	(922)
Net change in other financing activities	(1,108)	1,230
Net cash used in financing activities	(92,107)	(94,080)
Net (decrease) increase in cash, cash equivalents and restricted cash	(21,494)	7,714
Cash, cash equivalents and restricted cash, beginning of period	70,541	51,673
Cash, cash equivalents and restricted cash, end of period	49,047	59,387
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	34,508	44,623
Restricted cash	14,539	14,764
Cash, cash equivalents and restricted cash, end of period	49,047	59,387
Supplemental disclosure of cash flow information:
Interest paid	25,730	18,322
Income taxes paid	34	59
Supplemental disclosure of noncash investing and financing activities:
Conversion of OP Units to shares of common stock	450	336
Accrued construction in progress	25,878	15,155
Interest capitalized	1,391	388
Limited Partner [Member]
Cash flows from operating activities:
Net income	37,952	65,958
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	126,657	123,082
Loss on sale of depreciable real estate assets	29	13
Loss (gain) on sale of non-depreciable real estate assets	376	(8,963)
Loss on embedded derivative in preferred shares	27,638	524
Stock compensation expense	5,288	4,785
Amortization of debt issuance costs, discounts and premiums	1,157	1,747
Net change in operating accounts and other operating activities	(38,495)	(32,468)
Net cash provided by operating activities	160,602	154,678
Cash flows from investing activities:
Purchases of real estate and other assets	(5,004)	(13,595)
Capital improvements, development and other	(84,610)	(53,214)
Distributions from real estate joint ventures		43
Contributions to affiliates	(900)
Proceeds from disposition of real estate assets	525	13,882
Net cash used in investing activities	(89,989)	(52,884)
Cash flows from financing activities:
Proceeds from revolving credit facility	130,000	145,000
Repayments of revolving credit facility	(30,000)	(610,000)
Net repayments of commercial paper	(70,000)
Proceeds from notes payable		490,435
Principal payments on notes payable	(1,740)	(1,847)
Payment of deferred financing costs		(4,705)
Distributions paid on common shares/units	(118,337)	(113,271)
Distributions paid on preferred shares/units	(922)	(922)
Net change in other financing activities	(1,108)	1,230
Net cash used in financing activities	(92,107)	(94,080)
Net (decrease) increase in cash, cash equivalents and restricted cash	(21,494)	7,714
Cash, cash equivalents and restricted cash, beginning of period	70,541	51,673
Cash, cash equivalents and restricted cash, end of period	49,047	59,387
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	34,508	44,623
Restricted cash	14,539	14,764
Cash, cash equivalents and restricted cash, end of period	49,047	59,387
Supplemental disclosure of cash flow information:
Interest paid	25,730	18,322
Income taxes paid	34	59
Supplemental disclosure of noncash investing and financing activities:
Accrued construction in progress	25,878	15,155
Interest capitalized	$ 1,391	$ 388