Condensed Consolidated Statements of Income (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenues:
Rental revenue	$ 141,071		$ 284,488
Rental revenue		$ 124,038		$ 246,349
Tenant expense reimbursement	0	16,205	0	33,999
Observatory revenue	32,895	35,201	53,464	56,450
Lease termination fees	363	357	751	979
Third-party management and other fees	331	376	651	839
Other revenue and fees	1,584	2,352	4,183	7,184
Total revenues	176,244	178,529	343,537	345,800
Operating expenses:
Property operating expenses	40,227	39,418	83,182	83,603
Ground rent expenses	2,332	2,332	4,663	4,663
General and administrative expenses	15,998	13,225	30,024	25,853
Observatory expenses	8,360	7,678	15,935	15,014
Real estate taxes	28,267	26,743	56,499	53,487
Depreciation and amortization	44,821	39,468	90,919	79,351
Total operating expenses	140,005	128,864	281,222	261,971
Total operating income	36,239	49,665	62,315	83,829
Other income (expense):
Interest income	3,899	2,499	7,638	3,724
Interest expense	(20,597)	(20,525)	(41,286)	(38,116)
Income before income taxes	19,541	31,639	28,667	49,437
Income tax benefit (expense)	(611)	(1,455)	119	(1,195)
Net income	18,930	30,184	28,786	48,242
Private perpetual preferred unit distributions	(234)	(234)	(468)	(468)
Net income attributable to non-controlling interests	(7,609)	(13,299)	(11,554)	(21,355)
Net income attributable to common stockholders	$ 11,087	$ 16,651	$ 16,764	$ 26,419
Total weighted average shares:
Basic (in shares)	176,796	165,256	176,495	164,311
Diluted (in shares)	298,131	297,244	298,100	297,029
Earnings per share attributable to common stockholders:
Basic (in USD per share)	$ 0.06	$ 0.10	$ 0.09	$ 0.16
Diluted (in USD per share)	0.06	0.10	0.09	0.16
Dividends per share (in USD per share)	$ 0.105	$ 0.105	$ 0.210	$ 0.210