Schedule III Real Estate and Accumulated Depreciation (Details) (USD $)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	$ 172,716,000
Land	425,814,000
Building and Improvements	977,220,000
Building and Improvements	13,552,000
Real Estate, Gross	1,414,959,000	[1],[2]
Accumulated Depreciation	31,715,000	[3],[4]	9,476,000	3,109,000	500,000
Credit facility	305,000,000		19,995,000
Real Estate Investments, Acquired Intangible Assets, Total	127,800,000
Tax Basis of Investments, Cost for Income Tax Purposes	1,500,000,000
Finite-Lived Intangible Assets, Accumulated Amortization	9,500,000
Tangible Real Estate Investment Property, at Cost	1,414,959,000		322,205,000	115,035,000	61,294,000
Real Estate Investment Property, at Cost, Acquisitions	1,082,292,000		206,167,000	53,281,000
Real Estate, Improvements	12,089,000		1,003,000	460,000
Other Real Estate, Disposals	(1,627,000)		0	0
Real Estate Accumulated Depreciation, Depreciation Expense	23,405,000		6,367,000	2,609,000
Buildings, Useful Life	40 years 0 months 0 days
Land Improvements, Useful Life	15 years 0 months 0 days
Interior Design Building [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	20,582,000
Land	11,243,000
Building and Improvements	18,884,000
Building and Improvements	1,820,000
Real Estate, Gross	31,947,000	[1],[2]
Accumulated Depreciation	3,005,000	[3],[4]
Bleecker Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	21,300,000
Land	0
Building and Improvements	31,167,000
Building and Improvements	0
Real Estate, Gross	31,167,000	[1],[2]
Accumulated Depreciation	4,102,000	[3],[4]
Foot Locker [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	3,250,000
Land	2,753,000
Building and Improvements	2,753,000
Building and Improvements	0
Real Estate, Gross	5,506,000	[1],[2]
Accumulated Depreciation	364,000	[3],[4]
Regal Parking Garage [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	3,000,000
Land	0
Building and Improvements	4,637,000
Building and Improvements	0
Real Estate, Gross	4,637,000	[1],[2]
Accumulated Depreciation	533,000	[3],[4]
Duane Reed [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	8,400,000
Land	4,443,000
Building and Improvements	8,252,000
Building and Improvements	0
Real Estate, Gross	12,695,000	[1],[2]
Accumulated Depreciation	1,114,000	[3],[4]
Washington Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	4,831,000
Land	0
Building and Improvements	8,979,000
Building and Improvements	580,000
Real Estate, Gross	9,559,000	[1],[2]
Accumulated Depreciation	1,052,000	[3],[4]
One Jackson Square [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	13,000,000
Land	0
Building and Improvements	21,466,000
Building and Improvements	66,000
Real Estate, Gross	21,532,000	[1],[2]
Accumulated Depreciation	2,262,000	[3],[4]
42nd Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	11,365,000
Land	0
Building and Improvements	19,869,000
Building and Improvements	83,000
Real Estate, Gross	19,952,000	[1],[2]
Accumulated Depreciation	1,684,000	[3],[4]
Kings Highway Portfolio [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	20,200,000
Land	17,112,000
Building and Improvements	17,947,000
Building and Improvements	0
Real Estate, Gross	35,059,000	[1],[2]
Accumulated Depreciation	1,388,000	[3],[4]
163 Washington Ave Condominiums [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	0	[5]
Land	6,257,000
Building and Improvements	25,030,000
Building and Improvements	45,000
Real Estate, Gross	31,332,000	[1],[2]
Accumulated Depreciation	1,734,000	[3],[4]
1623 Kings Highway Portfolio [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	7,288,000
Land	3,440,000
Building and Improvements	8,538,000
Building and Improvements	27,000
Real Estate, Gross	12,005,000	[1],[2]
Accumulated Depreciation	490,000	[3],[4]
256 West 38th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	24,500,000
Land	20,000,000
Building and Improvements	26,483,000
Building and Improvements	1,653,000
Real Estate, Gross	46,970,000	[1],[2],[6]
Accumulated Depreciation	1,461,000	[3],[4]
229 West 36th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	35,000,000
Land	27,400,000
Building and Improvements	22,308,000
Building and Improvements	0
Real Estate, Gross	49,247,000	[1],[2],[6]
Accumulated Depreciation	1,279,000	[3],[4]
350 Bleecker Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	0	[5]
Land	0
Building and Improvements	11,783,000
Building and Improvements	0
Real Estate, Gross	11,783,000	[1],[2]
Accumulated Depreciation	568,000	[3],[4]
218 West 18th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	0	[5]
Land	17,500,000
Building and Improvements	90,869,000
Building and Improvements	2,028,000
Real Estate, Gross	110,397,000	[1],[2]
Accumulated Depreciation	3,655,000	[3],[4]
50 Varick Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	0
Land	0
Building and Improvements	77,992,000
Building and Improvements	7,250,000
Real Estate, Gross	85,242,000	[1],[2]
Accumulated Depreciation	2,158,000	[3],[4]
333 West 34th Street [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	0	[5]
Land	98,600,000
Building and Improvements	120,908,000
Building and Improvements	0
Real Estate, Gross	219,508,000	[1],[2]
Accumulated Depreciation	4,390,000	[3],[4]
Viceroy [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	0
Land	0
Building and Improvements	169,945,000
Building and Improvements	0
Real Estate, Gross	169,945,000	[1],[2]
Accumulated Depreciation	476,000	[3],[4]
1440 Broadway [Member]
Real Estate and Accumulated Depreciation [Line Items]
Encumbrances at December 31, 2013	0	[5]
Land	217,066,000
Building and Improvements	289,410,000
Building and Improvements	0
Real Estate, Gross	506,476,000	[1],[2]
Accumulated Depreciation	0	[3],[4]
Disposal [Member]
Real Estate and Accumulated Depreciation [Line Items]
Real Estate Accumulated Depreciation, Depreciation Expense	$ (1,166,000)		$ 0	$ 0
Maximum [Member]
Real Estate and Accumulated Depreciation [Line Items]
Fixtures, Useful life	15 years 0 months 0 days

[1] Acquired intangible lease assets allocated to individual properties in the amount of $127.8 million are not reflected in the table above.

[2] The tax basis of aggregate land, buildings and improvements as of December 31, 2013 is $1.5 billion.

[3] The accumulated depreciation column excludes $9.5 million of amortization associated with acquired intangible lease assets.

[4] Each of the properties has a depreciable life of: 40 years for buildings, 15 years for land improvements and five to 15 years for fixtures.

[5] These properties collateralize the credit facility, which had $305.0 million outstanding as of December 31, 2013.

[6] Gross amount is net of tenant improvement and building improvement dispositions of $1.6 million due to tenant lease terminations.