Condensed Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenues:
Rental revenue	$ 106,152		$ 288,566
Tenant expense reimbursement	20,034		49,491
Observatory revenue	35,684		83,374
Construction revenue	5,804		33,730
Third-party management and other fees	561		1,925
Other revenue and fees	1,206		7,829
Total revenues	169,441	62,278	464,915	184,267
Operating expenses:
Property operating expenses	38,291		109,300
Ground rent expenses	2,066		2,964
Marketing, general, and administrative expenses	10,071		29,786
Observatory expenses	7,109		21,210
Construction expenses	6,095		33,173
Real estate taxes	21,870		58,429
Formation transaction expenses	0		0
Acquisition expenses	2,647	0	3,382	0
Depreciation and amortization	37,880		96,632
Total operating expenses	126,029		354,876
Total operating income	43,412		110,039
Other income (expense):
Equity in net income of non-controlled entities	0	14,816	0	14,816
Interest expense	(17,674)		(46,640)
Income before income taxes	25,738		63,399
Income tax expense	(3,004)		(4,153)
Net income	22,734	2,281	59,246	7,282
Private perpetual preferred unit distributions	(241)		(241)
Net income attributable to non-controlling interests	(14,171)		(36,480)
Net income attributable to common stockholders	8,322		22,525
Total weighted average shares:
Basic	97,729		96,226
Diluted	263,041		250,696
Earnings per share attributable to common stockholders:
Basic	$ 0.09		$ 0.23
Diluted	$ 0.09		$ 0.23
Dividends per share	$ 0.085		$ 0.255
Predecessor [Member]
Revenues:
Rental revenue		45,228		134,133
Tenant expense reimbursement		7,180		20,814
Observatory revenue		0		0
Construction revenue		5,869		18,269
Third-party management and other fees		884		5,067
Other revenue and fees		3,117		5,984
Total revenues		62,278		184,267
Operating expenses:
Property operating expenses		14,170		40,128
Marketing, general, and administrative expenses		9,633		22,807
Observatory expenses		0		0
Construction expenses		5,933		18,722
Real estate taxes		8,003		23,790
Formation transaction expenses		1,507		4,507
Depreciation and amortization		12,763		38,030
Total operating expenses		52,009		147,984
Total operating income		10,269		36,283
Other income (expense):
Equity in net income of non-controlled entities		6,918		14,816
Interest expense		(14,906)		(43,817)
Income before income taxes		2,281		7,282
Net income		2,281		7,282
Net income attributable to the predecessor		$ (2,281)		$ (7,282)