Earnings (Loss) per Share and Equity Transactions - Reconciliation of Basic and Diluted Income per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Numerator:
Net income (loss) from continuing operations	$ 1,677	$ 24,926	$ (11,420)	$ 35,205
Earnings allocated to unvested restricted shares	0	(50)	0	0
Net income (loss) from continuing operations attributed to common shareholders	1,677	24,876	(11,420)	35,205
Net loss from discontinued operations attributed to common shareholders	$ 0	$ 0	$ 0	$ (25,500)
Denominator:
Weighted average number of common shares outstanding - basic (in shares)	718,934,723	728,722,763	720,198,772	728,645,975
Effect of unvested restricted shares (in shares)	633,616	733,959	0	575,251
Weighted average number of common shares outstanding - diluted (in shares)	719,568,339	729,456,722	720,198,772	729,221,226
Basic and diluted income (loss) per common share:
Net income (loss) from continuing operations per common share (in dollars per share)	$ 0	$ 0.03	$ (0.02)	$ 0.05
Net loss from discontinued operations per common share (in dollars per share)	0	0	0	(0.03)
Net income (loss) per common share, basic and diluted (in dollars per share)	$ 0	$ 0.03	$ (0.02)	$ 0.02

Undistributed Income (Loss) From Continuing Operations Allocated to Common Stockholders

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Undistributed Income (Loss) From Continuing Operations Allocated to Unvested Shares

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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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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Amount after tax of income (loss) from continuing operations attributable to the parent.

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The amount of net income (loss) from continuing operations per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

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Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Per basic and diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation, when the per share amount is the same.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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