Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenues:
Rental revenue	$ 112,866	$ 92,210	$ 222,924	$ 182,414
Tenant expense reimbursement	18,582	14,304	36,782	29,457
Observatory revenue	30,600	30,389	48,823	47,690
Construction revenue	374	12,963	1,981	27,926
Third-party management and other fees	594	753	1,040	1,364
Other revenue and fees	1,757	4,549	5,105	6,623
Total revenues	164,773	155,168	316,655	295,474
Operating expenses:
Property operating expenses	37,935	35,149	80,387	71,009
Ground rent expenses	2,332	447	4,663	898
Marketing, general, and administrative expenses	9,113	9,560	18,213	19,715
Observatory expenses	7,420	7,120	14,397	14,101
Construction expenses	353	12,795	3,222	27,078
Real estate taxes	22,952	18,186	45,930	36,559
Acquisition expenses	0	735	0	735
Depreciation and amortization	39,629	28,637	81,047	58,752
Total operating expenses	119,734	112,629	247,859	228,847
Total operating income	45,039	42,539	68,796	66,627
Other income (expense):
Interest expense	(17,571)	(14,629)	(33,618)	(28,966)
Income before income taxes	27,468	27,910	35,178	37,661
Income tax expense	(883)	(2,629)	(705)	(1,149)
Net income	26,585	25,281	34,473	36,512
Private perpetual preferred unit distributions	(234)	0	(468)	0
Net income attributable to non-controlling interests	(15,231)	(15,447)	(19,747)	(22,309)
Net income attributable to common stockholders	$ 11,120	$ 9,834	$ 14,258	$ 14,203
Total weighted average shares:
Basic (in shares)	112,852	95,466	111,136	95,466
Diluted (in shares)	265,867	244,436	265,866	244,431
Earnings per share attributable to common stockholders:
Basic (USD per share)	$ 0.10	$ 0.10	$ 0.13	$ 0.15
Diluted (USD pre share)	0.10	0.10	0.13	0.15
Dividends per share	$ 0.085	$ 0.085	$ 0.17	$ 0.17