Investments in Non-controlled Entities Summary of Financial Information of Non-consolidated Entities - Statements of Operations (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2012
Revenue:
Rental revenue and other		$ 139,646,000
Observatory revenue		76,680,000
Total revenue		216,326,000
Expenses:
Operating expenses—rental		112,711,000
Operating expenses—overage rent		11,000,000
Operating expenses—observatory		17,150,000
Interest		5,960,000
Depreciation and amortization		17,574,000
Total expenses		164,395,000
Net income (loss)		51,931,000
Our predecessor's share of equity in net income (loss) of non-controlled entities	0	14,816,000	0	14,816,000
Equity Method Investments	0	88,304,000	0	88,304,000	76,879,000
Empire State Building Co. [Member]
Revenue:
Rental revenue and other		98,561,000
Observatory revenue		76,680,000
Total revenue		175,241,000
Expenses:
Operating expenses—rental		89,117,000
Operating expenses—overage rent		10,894,000
Operating expenses—observatory		17,150,000
Interest		0
Depreciation and amortization		10,997,000
Total expenses		128,158,000
Net income (loss)		47,083,000
Our predecessor's share of equity in net income (loss) of non-controlled entities		13,612,000
1333 Broadway Associates [Member]
Revenue:
Rental revenue and other		11,357,000
Observatory revenue		0
Total revenue		11,357,000
Expenses:
Operating expenses—rental		5,669,000
Operating expenses—overage rent		0
Operating expenses—observatory		0
Interest		3,548,000
Depreciation and amortization		2,186,000
Total expenses		11,403,000
Net income (loss)		(46,000)
Our predecessor's share of equity in net income (loss) of non-controlled entities		(23,000)
1350 Broadway Associates [Member]
Revenue:
Rental revenue and other		16,076,000
Observatory revenue		0
Total revenue		16,076,000
Expenses:
Operating expenses—rental		7,825,000
Operating expenses—overage rent		0
Operating expenses—observatory		0
Interest		2,412,000
Depreciation and amortization		3,264,000
Total expenses		13,501,000
Net income (loss)		2,575,000
Our predecessor's share of equity in net income (loss) of non-controlled entities		1,104,000
501 Seventh Avenue Associates [Member]
Revenue:
Rental revenue and other		13,652,000
Observatory revenue		0
Total revenue		13,652,000
Expenses:
Operating expenses—rental		10,100,000
Operating expenses—overage rent		106,000
Operating expenses—observatory		0
Interest		0
Depreciation and amortization		1,127,000
Total expenses		11,333,000
Net income (loss)		2,319,000
Our predecessor's share of equity in net income (loss) of non-controlled entities		$ 123,000