Common Stock and Stockholders' Equity - Fair Value Assumptions (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Fair value assumptions
Risk-free interest rate, maximum	0.51%
Other disclosures
Compensation expense	$ 86,300	$ 18,315
Stock options
Fair value assumptions
Volatility, minimum (as a percent)	57.02%	46.10%
Volatility, maximum (as a percent)	57.49%	47.90%
Expected life (in years)	4 years 1 month 6 days	4 years 3 months 18 days
Risk-free interest rate, minimum	0.31%	0.87%
Risk-free interest rate, maximum		1.64%
Dividend yield (as a percent)	0.00%	0.00%
Weighted-average fair value of the underlying stock options	$ 107.06	$ 42.06
Other disclosures
Compensation expense	$ 28,200	$ 3,900
Unrecognized compensation cost	$ 97,200
Period over which unrecognized compensation cost is expected to be recognized	1 year 1 month 6 days

The weighted-average fair value of the underlying stock options.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Name Accounting Standards Codification
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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