Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2015

Fair Value Measurements [Abstract]

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

			As of March 31, 2015
(Amounts in thousands)			Total		Level 1		Level 2		Level 3
	Marketable securities		$	45,139	$	45,139	$	-	$	-
	Short-term investments			24,998		24,998		-		-
	Interest rate cap (included in other assets)			6		-		6		-
		Total assets	$	70,143	$	70,137	$	6	$	-
			As of December 31, 2014
(Amounts in thousands)			Total		Level 1		Level 2		Level 3
	Marketable securities		$	44,646	$	44,646	$	-	$	-
	Short-term investments			24,998		24,998		-		-
	Interest rate cap (included in other assets)			11		-		11		-
		Total assets	$	69,655	$	69,644	$	11	$	-

Fair Value, by Balance Sheet Grouping [Table Text Block]

		As of March 31, 2015				As of December 31, 2014
		Carrying		Fair		Carrying		Fair
(Amounts in thousands)		Amount		Value		Amount		Value
Assets:
	Cash equivalents	$	224,595	$	224,595	$	111,590	$	111,590
Liabilities:
	Mortgages payable	$	1,032,004	$	1,022,000	$	1,032,780	$	1,025,000
	Leasing commissions (included in amounts due to Vornado)		36		36		-		-
		$	1,032,040	$	1,022,036	$	1,032,780	$	1,025,000