Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Parent Company [Member]
Allowance for doubtful accounts receivable	$ 12,279	$ 9,021
Deferred costs accumulated amortization	91,213	83,529
Accumulated amortization of acquired lease intangible assets	123,662	56,695
Accumulated accretion of acquired lease intangible liabilities	$ 49,968	$ 23,538
Preferred stock, par value per share	$ 0.01	$ 0.01
Preferred stock, shares authorized	30,000,000	30,000,000
Preferred units of Series 6-7, units issued	0	13,000,000
Preferred units of Series 6-7, units outstanding	0	13,000,000
Preferred stock, liquidation preferences per share	$ 0	$ 25
Common stock, par value per share	$ 0.01	$ 0.01
Common stock, shares authorized	220,000,000	150,000,000
Common stock, shares issued	170,109,043	104,497,286
Exchangeable operating partnership units aggregate redemption value	$ 21,708	$ 10,630
Treasury stock, shares held at cost	359,784	347,903
Partnership Interest [Member]
Allowance for doubtful accounts receivable	$ 13,412	$ 9,021
Deferred costs accumulated amortization	91,213	83,529
Accumulated amortization of acquired lease intangible assets	123,662	56,695
Accumulated accretion of acquired lease intangible liabilities	$ 49,968	$ 23,538
Preferred units of general partner par value per unit	$ 0.01	$ 0.01
Preferred units of Series 6-7, units issued	0	13,000,000
Preferred units of Series 6-7, units outstanding	0	13,000,000
Preferred stock, liquidation preferences per share	$ 0	$ 25
General partner units, outstanding	170,109,043	104,497,286
Limited partner units, outstanding	349,902	154,170