Acquisitions, Dispositions, Discontinued Operations and Assets Held for Sale Acquisitions, Dispositions, Discontinued Operations and Assets Held for Sale (Income from Discontinued Operations) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property revenues		$ 14,827
Property expenses		(5,148)
Property revenues less property expenses		9,679
Property management expense		(176)
Depreciation and amortization		(4,327)
Income tax expense		(100)
Income from discontinued operations	$ 0	$ 5,076

Acquisitions, Dispositions, Discontinued Operations and Assets Held for Sale Acquisitions, Dispositions, Discontinued Operations and Assets Held for Sale (Income from Discontinued Operations) (Details) - USD ($)
$ in Thousands

3 Months Ended

Mar. 31, 2017

Mar. 31, 2016

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Property revenues

$ 14,827

Property expenses

(5,148)

Property revenues less property expenses

9,679

Property management expense

(176)

Depreciation and amortization

(4,327)

Income tax expense

(100)

Income from discontinued operations

$ 0

$ 5,076