Assets Held For Sale and Sales of Real Estate Narrative (Details) $ in Thousands						3 Months Ended		6 Months Ended
	Jul. 14, 2016 USD ($)	Jul. 12, 2016 USD ($) property	Jul. 07, 2016 USD ($)	Jun. 02, 2016 USD ($)	May 02, 2016 USD ($)	Jun. 30, 2016 USD ($) property	Mar. 31, 2016 USD ($)	Jun. 30, 2016 USD ($) property	Jun. 30, 2015 USD ($) property	Dec. 31, 2015 USD ($)
Long Lived Assets Held-for-sale [Line Items]
Number of real estate properties held for sale (property) | property						15		15
Assets held for sale						$ 295,542		$ 295,542		$ 206,422	[1]
Impairment charges						7,000	$ 8,000
Proceeds from sale of real estate									$ 5,000
Gain (Loss) on sale of real estate						(449)		(449)	$ (97)
Number of real estate properties sold (property) | property									2
Marquee Properties
Long Lived Assets Held-for-sale [Line Items]
Assets held for sale						206,000		206,000		$ 206,000
Allentown Property
Long Lived Assets Held-for-sale [Line Items]
Proceeds from sale of real estate				$ 8,000
Deerfield Beach Property
Long Lived Assets Held-for-sale [Line Items]
Proceeds from sale of real estate					$ 24,000
Subsequent Event | Seattle Property
Long Lived Assets Held-for-sale [Line Items]
Proceeds from sale of real estate			$ 19,000
Gain (Loss) on sale of real estate			$ 8,000
Subsequent Event | Orlando Sentinel Property
Long Lived Assets Held-for-sale [Line Items]
Proceeds from sale of real estate		$ 34,000
Gain (Loss) on sale of real estate		$ 2,000
Number of real estate properties sold (property) | property		2
Subsequent Event | Arlington Heights Property
Long Lived Assets Held-for-sale [Line Items]
Proceeds from sale of real estate	$ 400
Real Estate
Long Lived Assets Held-for-sale [Line Items]
Net book value of properties						$ 11,000		$ 11,000

[1] (1) December 31, 2015 balances have been reclassified to present debt issuance costs as a direct deduction from the carrying amount of an associated debt liability in accordance with ASU 2015-03. See Note 1 for further information.