Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net income		$ 40,525	$ 35,989
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization		70,224	63,734
Loss on early retirement of debt		0	323
Distributions of income from joint ventures		1,815	1,720
Equity in income of joint ventures	[1]	(1,829)	(1,817)
Share-based compensation		4,183	4,449
Net change in operating accounts and other		(27,764)	(31,413)
Net cash from operating activities		87,154	72,985
Cash flows from investing activities
Development and capital improvements		(71,828)	(62,783)
Acquisition of operating property		(201,899)	0
Maturities of short-term investments		0	100,000
Other		(1,830)	(2,442)
Net cash from investing activities		(275,557)	34,775
Cash flows from financing activities
Repayment of notes payable		(358)	(31,214)
Distributions to common shareholders and non-controlling interests		(72,943)	(69,161)
Other		336	493
Net cash from financing activities		(72,965)	(99,882)
Net increase (decrease) in cash, cash equivalents, and restricted cash		(261,368)	7,878
Total cash, cash equivalents, and restricted cash, beginning of year		377,805	245,826
Total cash, cash equivalents, and restricted cash, end of period		116,437	253,704
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Total cash, cash equivalents, and restricted cash		377,805	245,826
Supplemental information
Cash paid for interest, net of interest capitalized		16,701	15,767
Supplemental schedule of noncash investing and financing activities
Distributions declared but not paid		75,083	69,236
Value of shares issued under benefit plans, net of cancellations		16,471	16,934
Accrual associated with construction and capital expenditures		$ 23,204	$ 16,685

[1] Equity in income excludes our ownership interest of fee income from various services provided by us to the Funds.