Net Loss per Share Attributable to Common Stock - Computation of Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Numerator:
Net loss	$ (7,895)	$ (12,625)	$ (68,012)	$ (79,804)
Denominator:
Weighted average shares —basic and diluted (in shares)	98,785,318	91,216,886	96,114,012	90,915,334
Net loss per share attributable to common stock—basic and diluted (in dollars per share)	$ (0.08)	$ (0.14)	$ (0.71)	$ (0.88)
Temporary Equity, Dividends, Adjustment	$ 1,284	$ 0	$ 1,284	$ 0
Net loss	$ (6,611)	$ (12,625)	$ (66,728)	$ (79,804)

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, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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Accretion of temporary equity during the period due to cash, stock, and in-kind dividends. This item is an adjustment to net income necessary to derive net income apportioned to common stockholders and is to be distinguished from Temporary Equity, Accretion of Dividends (Temporary Equity, Accretion of Dividends).

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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