Share-Based Compensation and Other Benefit Plans - Fair Value of Each Award Estimated on Date of Grant Using Black-Scholes-Merton Option-Pricing Formula (Detail) - $ / shares	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Performance Restricted Stock Units
Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]
Expected volatility, min	131.74%	101.32%
Expected volatility, max	134.74%	117.71%
Expected volatility			49.90%
Dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate, min	0.22%	0.18%
Risk-free interest rate, max	0.29%	0.51%
Risk-free interest rate			1.66%
Average grant-date fair value (in dollars per share)	$ 22.44
Granted (in shares)	225,206	145,399	15,066
Performance Shares \| Share-based Payment Arrangement, Tranche One
Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]
Average grant-date fair value (in dollars per share)			$ 34.02
Performance Shares \| Share-based Payment Arrangement, Tranche One \| Minimum
Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]
Average grant-date fair value (in dollars per share)	$ 17.74	$ 2.40
Performance Shares \| Share-based Payment Arrangement, Tranche One \| Maximum
Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]
Average grant-date fair value (in dollars per share)	33.31	$ 16.02
ROCE
Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]
Average grant-date fair value (in dollars per share)	$ 13.63

Schedule of Benefit Obligations Weighted Average Assumptions [Line Items]

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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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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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 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 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 risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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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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