Fair Value Measurements (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended								3 Months Ended		9 Months Ended		0 Months Ended	9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014 Maximum [Member]	Sep. 30, 2013 Maximum [Member]	Sep. 30, 2014 Minimum [Member]	Sep. 30, 2013 Minimum [Member]	Sep. 30, 2014 Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2013 Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2014 Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2013 Fair Value, Measurements, Nonrecurring [Member]	May 08, 2014 A-T-T St. Louis, St. Louis, Missouri [Member]	Sep. 30, 2013 AT&T Hoffman Estates [Member]	Sep. 30, 2013 AT&T Hoffman Estates [Member] Maximum [Member]	Sep. 30, 2013 AT&T Hoffman Estates [Member] Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate					4.83%
Discounted cash flow method, term					10 years		10 years
Investment properties, capitalization rates									9.00%	10.50%	6.00%	6.80%							7.75%	6.25%
Investment properties, discount rates									9.25%	12.00%	6.75%	7.50%							8.50%	7.00%
Disposal Date																	May 08, 2014
Provision for asset impairment	$ 2,337	[1]	$ 39,942	[2]	$ 80,281	[3]	$ 225,009	[4]					$ 2,337	$ 39,942	$ 80,281	$ 225,009	$ 67,647	$ 147,480
Provision for asset impairment for disposed properties	$ 0		$ 0		$ 0		$ 4,476

[1] Total provision for asset impairment included $1,667 related to one lodging property and $670 related to one non-core property.

[2] Total provision for asset impairment included $26,175 related to two lodging properties, $11,723 related to three retail properties and $2,044 related to four non-core properties.

[3] Total provision for asset impairment included $4,665 related to two lodging properties and $75,616 related to five non-core properties.

[4] Total provision for asset impairment included $26,175 related to two lodging properties, $21,179 related to four retail properties and $177,655 related to eleven non-core properties.