Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Net income	$ 89,734	$ 89,407
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	49,432	42,897
Amortization of deferred financing costs	3,103	2,823
Non-cash interest expense related to amortization of discount on equity component of exchangeable senior notes	1,269	1,233
Non-cash interest expense related to amortization of premium on notes payable	0	(354)
Compensation expense related to stock-based awards	1,990	1,710
Gain on sale of real estate assets and purchase of joint venture partner's interest	0	(26,923)
Loss on earnout from prior acquisition	0	(1,544)
Distributions from unconsolidated real estate ventures in excess of earnings	1,123	998
Changes in operating assets and liabilities:
Receivables from related parties and affiliated real estate joint ventures	(1,438)	(2,878)
Other assets	4,336	(5,276)
Accounts payable and accrued expenses	(30,069)	(5,642)
Other liabilities	(6,359)	(985)
Net Cash Provided by (Used in) Operating Activities	113,121	95,466
Cash flows from investing activities:
Acquisition of real estate assets	(39,136)	(234,820)
Development and redevelopment of real estate assets	(5,246)	(6,543)
Change in restricted cash	1,653	(1,265)
Investment in unconsolidated real estate ventures	(1,519)	(4,794)
Return of investment in unconsolidated real estate ventures	581	318
Purchase/issuance of notes receivable	0	(10,656)
Principal payments received from notes receivable	44,869	0
Purchase of equipment and fixtures	(1,292)	(908)
Net Cash Provided by (Used in) Investing Activities	(90)	(258,668)
Cash flows from financing activities:
Proceeds from the sale of common stock, net of offering costs	0	73,574
Repurchase of exchangeable senior notes	0	(19,639)
Proceeds from notes payable and revolving lines of credit	169,000	195,976
Principal payments on notes payable and revolving lines of credit	(187,916)	(32,859)
Deferred financing costs	(253)	(1,286)
Net proceeds from exercise of stock options	0	13
Proceeds from termination of interest rate cap	0	1,650
Redemption of Operating Partnership units held by noncontrolling interests	(1,754)	0
Dividends paid on common stock	(98,212)	(73,827)
Distributions to noncontrolling interests	(8,443)	(6,446)
Net cash provided by (used in) financing activities	(127,578)	137,156
Net decrease in cash and cash equivalents	(14,547)	(26,046)
Cash and cash equivalents, beginning of the period	43,858	75,799
Cash and cash equivalents, end of the period	29,311	49,753
Supplemental schedule of cash flow information
Interest paid	37,570	24,873
Income taxes paid	5,059	4,835
Redemption of Operating Partnership units held by noncontrolling interests for common stock
Noncontrolling interests in Operating Partnership	0	(12)
Common stock and paid-in capital	0	12
Tax effect from vesting of restricted stock grants and option exercises
Other assets	0	272
Additional paid-in capital	0	(272)
Accrued construction costs and capital expenditures
Acquisition of real estate assets	4,797	0
Development and redevelopment of real estate assets	990	0
Other liabilities	(5,787)	0
Distribution of real estate from investments in unconsolidated real estate ventures
Real estate assets, net	0	17,261
Investments in unconsolidated real estate ventures	$ 0	$ (17,261)