Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Numerator:
Net (loss) income attributable to stockholders - basic	$ (13,228)	$ (8,232)	$ (26,179)	$ (8,319)
Net (loss) income attributable to convertible OP units	(3,180)	(144)	(6,270)	(144)
Net (loss) income - diluted	$ (16,408)	$ (8,376)	$ (32,449)	$ (8,463)
Denominator:
Weighted-average shares - basic	183,699,000	183,843,000	184,676,000	183,402,000
OP units	44,453,000	2,649,000	44,453,000	2,739,000
Adjusted weighted-average shares - diluted	228,152,000	186,492,000	229,129,000	186,141,000
Earnings per common share:
Net loss attributable to stockholders - basic and diluted	$ (0.07)	$ (0.04)	$ (0.14)	$ (0.05)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Class B units unvested	0	2,700,000	0	2,700,000
Stock Compensation Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Unvested restricted stock awards, granted	1,000,000		1,000,000

Represents the number of unvested Class B units that are outstanding.

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Amount after income tax of income (loss) including the portion attributable to redeemable noncontrolling interest. Excludes the portion attributable to nonredeemable noncontrolling interest.

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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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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or 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 portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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