Stockholders' Equity - Summary of MSU Performance (Detail) - Market Performance Based Restricted Stock Units - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Number of Shares
Nonvested beginning balance (shares)	227,000
Granted (shares)	177,000
Vested and released (shares)	(229,877)
Nonvested ending balance (shares)	174,000	227,000
Nonvested (usd per share)	$ 551.57	$ 430.50
Granted (usd per share)	658.02
Vested and released (usd per share)	$ 513.73
Weighted Average Remaining Contractual Term
Nonvested	1 year
Aggregate Intrinsic Value
Unvested	$ 114,414

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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