Fair Value of Financial Instruments (Fair Value of Assets and Liabilities, Measured on a Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap assets	$ 5,509	$ 9,189	[1]
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in real estate fund		1,484
CMBS	58,646	60,583
Interest rate swap assets	5,509	9,189
Total assets	64,155	71,256
Interest rate swap liabilities	(7,384)	(1,719)
Series D Preferred Stock embedded derivative		(16,736)
Total liabilities		(18,455)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in real estate fund		0
CMBS	0	0
Interest rate swap assets	0	0
Total assets	0	0
Interest rate swap liabilities	0	0
Series D Preferred Stock embedded derivative		0
Total liabilities		0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in real estate fund		1,484
CMBS	0	0
Interest rate swap assets	5,509	9,189
Total assets	5,509	10,673
Interest rate swap liabilities	(7,384)	(1,719)
Series D Preferred Stock embedded derivative		0
Total liabilities		(1,719)
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments in real estate fund		0
CMBS	58,646	60,583
Interest rate swap assets	0	0
Total assets	58,646	60,583
Interest rate swap liabilities	0	0
Series D Preferred Stock embedded derivative		(16,736)
Total liabilities		$ (16,736)

[1] December 31, 2013 line items have been broken out since the previously filed presentation to conform with current presentation and provide detailed balances relating to derivative assets, prepaid expenses, and deferred costs.