Stock Compensation Plans - SSAR's and Stock Option Activity (Detail) - SSAR's and Stock Options [Member] - $ / shares shares in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Shares Subject to SSARs/Options
Beginning balance (in shares)	42
Granted (in shares)	3
Exercised (in shares)	(90)
Cancelled (in shares)	(9)
Assumed (in shares)	341
Ending balance (in shares)	287	42
Weighted Average Exercise Price
Beginning balance (in dollars per share)	$ 135.01
Granted (in dollars per share)	144.67
Exercised (in dollars per share)	110.28
Cancelled (in dollars per share)	101.19
Assumed (in dollars per share)
Ending balance (in dollars per share)	$ 107.48	$ 135.01
SSARs/ Options Exercisable (in shares)	235	1
Expected to Vest (in shares)	44
Expected to Vest (in dollars per share)	$ 95.94

Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Assumptions In Period

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Assumptions In Period, Weighted Average Exercise Price

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No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

+ References

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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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