Net Loss per Share - Numerators and Denominators of Basic and Diluted Net Loss per Share Computations for Common Stock (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Numerator:
Net loss	$ (1,033,660)	$ (1,255,911)	$ (3,445,066)
Basic shares:
Weighted-average common shares - Basic	1,375,462	1,300,568	1,166,085
Diluted shares:
Weighted-average common shares - Diluted	1,375,462	1,300,568	1,166,085
Net loss per share attributable to common stockholders:
Basic	$ (0.75)	$ (0.97)	$ (2.95)
Diluted	$ (0.75)	$ (0.97)	$ (2.95)
Class A Common Stock
Numerator:
Net loss	$ (817,156)	$ (921,235)	$ (2,169,120)
Net loss attributable to common stockholders	$ (817,156)	$ (921,235)	$ (2,169,120)
Basic shares:
Weighted-average common shares - Basic	1,087,366	953,992	734,203
Diluted shares:
Weighted-average common shares - Diluted	1,087,366	953,992	734,203
Net loss per share attributable to common stockholders:
Basic	$ (0.75)	$ (0.97)	$ (2.95)
Diluted	$ (0.75)	$ (0.97)	$ (2.95)
Class B Common Stock
Numerator:
Net loss	$ (33,341)	$ (94,897)	$ (548,098)
Net loss attributable to common stockholders	$ (33,341)	$ (94,897)	$ (548,098)
Basic shares:
Weighted-average common shares - Basic	44,366	98,271	185,520
Diluted shares:
Weighted-average common shares - Diluted	44,366	98,271	185,520
Net loss per share attributable to common stockholders:
Basic	$ (0.75)	$ (0.97)	$ (2.95)
Diluted	$ (0.75)	$ (0.97)	$ (2.95)
Class C Common Stock
Numerator:
Net loss	$ (183,164)	$ (239,779)	$ (727,848)
Net loss attributable to common stockholders	$ (183,164)	$ (239,779)	$ (727,848)
Basic shares:
Weighted-average common shares - Basic	243,730	248,305	246,362
Diluted shares:
Weighted-average common shares - Diluted	243,730	248,305	246,362
Net loss per share attributable to common stockholders:
Basic	$ (0.75)	$ (0.97)	$ (2.95)
Diluted	$ (0.75)	$ (0.97)	$ (2.95)

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 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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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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