Business Acquisition, Pro Forma Earnings Per Share [Abstract]

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Business Acquisition, Pro Forma Income (Loss) from Continuing Operations [Abstract]

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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Per basic share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period.

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Per diluted share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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Real Estate Investments - Pro Forma (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings (loss) per common share from continuing operations:
Basic -- as reported									$ 0.66	$ 0.19	$ (0.21)
Diluted -- as reported									0.65	0.19	(0.21)
Earnings (loss) per common share:
Basic -- as reported	$ 0.42	$ 0.11	$ 0.02	$ 0.11	$ (0.08)	$ 0.03	$ (0.02)	$ 0.25	0.66	0.19	(0.21)
Diluted -- as reported	$ 0.41	$ 0.11	$ 0.02	$ 0.11	$ (0.08)	$ 0.03	$ (0.02)	$ 0.25	$ 0.65	$ 0.19	$ (0.21)
Broadmoor Austin Associates [Member]
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Pro forma revenue											$ 612,649
Pro forma income (loss) from continuing operations											(36,704)
Pro forma net income (loss) available to common shareholders											$ (43,594)
Earnings (loss) per common share from continuing operations:
Basic -- as reported											$ (0.17)
Basic -- as pro forma											(0.21)
Diluted -- as reported											(0.17)
Diluted -- as pro forma											(0.21)
Earnings (loss) per common share:
Basic -- as reported											(0.21)
Basic -- as pro forma											(0.24)
Diluted -- as reported											(0.21)
Diluted -- as pro forma											$ (0.24)