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Share-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
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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

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