Stock-Based Incentive Plans - Additional Information (Detail) $ in Millions	9 Months Ended
Sep. 30, 2022 USD ($) plan shares	Dec. 31, 2021 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of current benefit plans \| plan	2
Number of benefit plans \| plan	9
Number of expired benefit plans \| plan	7
Restricted Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares, vesting period (in years)	3 years
Number of shares of restricted class A common stock outstanding (in shares)	1,339,445	1,706,121
Unrecognized compensation cost relating to nonvested share-based compensation \| $	$ 39.1
Unrecognized compensation cost expected to be recognized over weighted average period (in years)	1 year
Expired Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available under plan (in shares)	0
Vest in 2022 \| Restricted Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of restricted class A common stock outstanding (in shares)	252,556
Vest in 2023 \| Restricted Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of restricted class A common stock outstanding (in shares)	684,797
Vest in 2024 \| Restricted Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of restricted class A common stock outstanding (in shares)	402,092
Class A Common Stock \| Stock Incentive Current Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares available under plan (in shares)	10,400,000
Number of shares available under plan (in shares)	10,018,856

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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