Share-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized to issued as options (in shares)	2,700,000
Share-based compensation expense	$ 4,226	$ 2,822	$ 2,416
Unrecognized compensation costs related to unvested awards	$ 3,600
Unrecognized compensation costs, period for recognition	2 years 2 months 12 days
Term life of options	10 years
Number of options granted (in shares)	158,700	210,400	57,800
Weighted average grant date fair value of the options granted (in usd per share)	$ 4.76	$ 2.77	$ 10.60
Cash proceeds from the exercise of options	$ 0	$ 100	$ 300
Tax benefit recognized from stock option exercises		100	100
Total intrinsic value of options exercised		7	500
Selling, General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 800	$ 400	$ 200
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted vesting period	3 years
Stock units issued (in shares)	460,255	339,498	86,516
Fair value assumptions, exercise price (in dollars per share)	$ 9.35	$ 7.74	$ 24.55
Total grant-date fair value of restricted stock	$ 1,900	$ 2,900	$ 1,800
TSR Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock units issued (in shares)	139,000
Award performance period	36 months
Percentage of shares issuable based on threshold performance	50.00%
Percentage of shares issuable based on target performance	100.00%
Percentage of shares issuable based on maximum performance	150.00%
ROIC Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock units issued (in shares)	157,000
Percentage of shares issuable based on threshold performance	35.00%
Percentage of shares issuable based on target performance	100.00%
Percentage of shares issuable based on maximum performance	150.00%
Options awards vested (in shares)	0	0	0
Officers and Key Employees \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted vesting period	3 years	3 years	3 years
Non-executive Directors \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted vesting period	1 year	1 year	1 year
Changes in Vesting Estimates \| Selling, General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ (300)	$ (1,100)	$ (1,800)
Changes in Vesting Estimates \| Income (Loss) From Discontinued Operations, Net of Tax
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	(500)		(200)
Changes in Vesting Estimates \| ROIC Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividends accrued for performance share units	$ 100	$ 100	$ 100

Share-based Compensation Arrangement by Share-based Payment Award, Award Performance Period

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Share based compensation arrangement by share based payment award percentage of shares issuable based on threshold performance.

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Share based compensation arrangement by share based payment award terms of award.

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Share based compensation arrangement by share-based payment award percentage of shares issuable based on maximum performance.

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Share based compensation arrangement by share-based payment award, percentage of shares Issuable based on target performance.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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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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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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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 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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of options vested.

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