Property Dispositions (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($) property unit	Mar. 31, 2018 USD ($) property
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of properties held for sale | unit	1
Proceeds from sale of real estate investments	$ 82,533	$ 3,227
Gain (Loss) on Sale of Properties, Net of Applicable Income Taxes	16,490	96
Provision for impairment, net of tax	$ 1,672	$ 374
Wholly Owned Properties [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	100.00%	100.00%
Parent Company [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale of real estate investments	$ 82,533	$ 3,227
Gain (Loss) on Sale of Properties, Net of Applicable Income Taxes	16,490	96
Provision for impairment, net of tax	$ 1,672	$ 16,054
Operating Segments [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Real Estate Properties Sold | property	4	1
Land [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Real Estate Properties Sold | property	2	0