Consolidated and Combined Statements of Cash Flows - USD ($)		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
OPERATING ACTIVITIES:
Net income (loss)		$ (79,084,000)	$ 61,974,000	$ 49,628,000
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Share-based compensation expense		33,693,000	4,502,000	4,506,000
Depreciation and amortization, including amortization of debt issuance costs		164,580,000	135,072,000	146,985,000
Deferred rent		(10,388,000)	(15,551,000)	(10,929,000)
Loss from unconsolidated real estate ventures, net		4,143,000	947,000	4,283,000
Amortization of above- and below-market lease intangibles, net		(862,000)	(1,353,000)	(2,797,000)
Amortization of lease incentives		4,023,000	3,592,000	2,570,000
Return on capital from unconsolidated real estate ventures		2,563,000	1,520,000	1,348,000
Gain on bargain purchase		(24,376,000)	0	0
Loss on extinguishment of debt		701,000	0	0
Realized loss on interest rate swaps and caps		27,000	0	0
Unrealized gain on interest rate swaps and caps		(1,348,000)	0	0
Bad debt expense		3,807,000	750,600	1,407,000
Other non-cash items		3,928,000	6,236,000	626,000
Deferred tax benefit		(10,408,000)	0	0
Changes in operating assets and liabilities:
Tenant and other receivables		(2,098,000)	(3,693,000)	(428,000)
Other assets, net		(23,481,000)	(16,614,000)	(13,667,000)
Accounts payable and accrued expenses		16,160,000	7,667,000	(4,004,000)
Other liabilities, net		(7,397,000)	(25,509,000)	(1,298,000)
Net cash provided by operating activities		74,183,000	159,541,000	178,230,000
INVESTING ACTIVITIES:
Development costs, construction in progress and real estate additions		(210,593,000)	(237,814,000)	(234,285,000)
Cash and restricted cash received in connection with the Combination, net		97,416,000	0	0
Acquisition of interests in unconsolidated real estate ventures, net of cash acquired		(8,834,000)	0	0
Distributions of capital from unconsolidated real estate ventures		6,929,000	0	0
Investments in and advances to unconsolidated real estate ventures		(16,321,000)	(23,027,000)	(7,865,000)
Repayment of notes receivable		50,934,000	0	0
Other investments		(2,207,000)	(1,966,000)	(1,467,000)
Proceeds from repayment of receivable from former parent		75,000,000	4,000,000	7,000,000
Net cash used in investing activities		(7,676,000)	(258,807,000)	(236,617,000)
FINANCING ACTIVITIES:
Contributions from (distributions to) former parent, net		160,203,000		16,495,000
Contributions from (distributions to) former parent, net			(3,763,000)
Repayment of borrowings from former parent		(115,630,000)	0	(13,600,000)
Proceeds from borrowings from former parent		4,000,000	79,500,000	96,512,000
Capital lease payments		(17,827,000)	0	0
Borrowings under mortgages payable		366,239,000	0	341,460,000
Borrowings under revolving credit facility		115,751,000	0	0
Borrowings under unsecured term loan		50,000,000	0	0
Repayments of mortgages payable		(272,905,000)	(24,364,000)	(315,824,000)
Debt issuance costs		(19,287,000)	(70,000)	(2,359,000)
Dividends paid to common shareholders		(26,540,000)
Distributions to redeemable noncontrolling interests		(4,556,000)	0	0
Contributions from noncontrolling interests		357,000	0	0
Distributions to noncontrolling interests		(18,000)	(220,000)	(13,000)
Net cash provided by financing activities		239,787,000	51,083,000	122,671,000
Net increase (decrease) in cash and cash equivalents and restricted cash		306,294,000	(48,183,000)	64,284,000
Cash and cash equivalents and restricted cash at beginning of the year		32,263,000	80,446,000	16,162,000
Cash and cash equivalents and restricted cash at end of the year		338,557,000	32,263,000	80,446,000
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF THE YEAR:
Cash and cash equivalents and restricted cash		32,263,000	80,446,000	16,162,000
SUPPLEMENTAL DISCLOSURE OF CASH FLOW AND NON-CASH INFORMATION:
Transfer of mortgage payable to former parent		115,630,000	115,022,000	0
Cash paid for interest (net of capitalized interest of $12,727, $4,076 and $6,437 in 2017, 2016 and 2015)		52,388,000	45,373,000	54,055,000
Accrued capital expenditures included in accounts payable and accrued expenses		12,445,000	8,851,000	29,400,000
Write-off of fully depreciated assets		55,998,000	100,076,000	23,155,000
Accrued lease incentives		0	0	30,514,000
Cash payments for income taxes		3,396,000	1,165,000	677,000
Non-cash contributions from redeemable noncontrolling interests	[1]	5,420,000	0	0
Non-cash transactions related to the Formation Transaction:
Issuance of common limited partnership units at the Separation	[2]	96,632,000	0	0
Issuance of common shares at the Separation	[2]	2,330,579,000	0	0
Issuance of common shares in connection with the Combination	[2]	864,918,000	0	0
Issuance of common limited partnership units in connection with the Combination	[2]	359,967,000	0	0
Adjustment to record redeemable noncontrolling interest at redemption value	[2]	130,692,000	0	0
Contribution from former parent in connection with the Separation	[2]	$ 172,817,000	$ 0	$ 0

[1] See Note 11 for additional information.

[2] See Note 3 for information regarding assets, liabilities and noncontrolling interests acquired in the Formation Transaction.