Goodwill and Other Intangibles (Narrative) (Details) $ in Thousands		3 Months Ended	9 Months Ended	12 Months Ended
	Oct. 01, 2015 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) segment	Dec. 31, 2014 USD ($)
Related Party Transaction [Line Items]
Number of segments | segment				2
Impairment of intangible assets	$ 73,700			$ 73,700	$ 86,400
Amortization expense		$ 3,400	$ 22,500
Intangible assets		50,779		$ 50,779	150,359
Managed REITs [Member] | Management And Advisory Contracts [Member]
Related Party Transaction [Line Items]
Estimated useful life				4 years
Intangible assets		50,800		$ 50,800	150,400
Intangible assets, accumulated amortization		(3,400)		(3,400)	$ (16)
Estimated amortization expense, 2016		26,100		26,100
Estimated amortization expense, 2017		16,600		16,600
Estimated amortization expense, 2018		4,000		4,000
Estimated amortization expense, 2019		$ 3,800		3,800
Cole Capital Segment [Member]
Related Party Transaction [Line Items]
Impairment of intangible assets				$ 139,655