Convertible Notes, Net - Summary of Outstanding Convertible Senior Notes Footnotes (Detail) - Class A Common Stock	12 Months Ended
Dec. 31, 2021 USD ($) $ / shares
5.25% Convertible Senior Notes
Debt Instrument [Line Items]
Debt conversion, principal amount \| $	$ 1,000
4.38% Convertible Senior Notes
Debt Instrument [Line Items]
Debt conversion, principal amount \| $	$ 1,000
4.75% Convertible Senior Notes Issued In March 2018
Debt Instrument [Line Items]
Debt instrument, conversion price (in USD per share) \| $ / shares	$ 35.67
4.38% Convertible Senior Notes Issued in May 2017
Debt Instrument [Line Items]
Debt instrument, conversion price (in USD per share) \| $ / shares	$ 36.23

The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The price per share of the conversion feature embedded in the debt instrument.

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