Summary of Significant Accounting Policies - Reclassifications (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Reclassifications [Line Items]
Property operating expense	$ 44,135	$ 40,628	$ 127,691	$ 116,663
Bad debts, net of recoveries	(62)	4	42	175
Gain on sales of properties	1,288	(7)	30,879	39,525
INCOME FROM CONTINUING OPERATIONS	$ 6,548	3,173	$ 53,456	60,243
Income (loss) from discontinued operations		0		0
Gain on sales of properties		0		0
INCOME (LOSS) FROM DISCONTINUED OPERATIONS		0		0
As Previously Reported
Reclassifications [Line Items]
Property operating expense		40,626		116,644
Bad debts, net of recoveries		14		185
Gain on sales of properties		(7)		39,519
INCOME FROM CONTINUING OPERATIONS		3,165		60,247
Income (loss) from discontinued operations		8		(9)
Gain on sales of properties		0		5
INCOME (LOSS) FROM DISCONTINUED OPERATIONS		$ 8		$ (4)

Amount of expense incurred and directly related to generating revenue from leased and rented property or equipment.

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