Assets Held for Sale (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) ft²	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale - area of real estate | ft²	526,006
Impairment of real estate	$ 12,334	$ 6,311	$ 203
Net assets from asset held for sale
Total assets	59,412	31,260
Total liabilities	(2,860)	(2,476)
Total accumulated other comprehensive loss (gain)	536	768
Net assets classified as held for sale	$ 57,088	$ 29,552
Other markets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale - area of real estate | ft²	123,862