Share-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized to issued as options (in shares)	1,900,000
Share-based compensation expense	$ 2,416	$ 5,496	$ 3,935
Decrease in share-based compensation expense from change in vesting	(2,000)
Tax benefit for share-based compensation cost	700	$ 1,600	$ 600
Unrecognized compensation costs related to unvested awards	$ 4,000
Unrecognized compensation costs, period for recognition	1 year 10 months 6 days
Term life of options	10 years
Stock awards granted vesting period		3 years	3 years
Number of options granted	57,800	125,700	167,000
Weighted average grant date fair value of the options granted	$ 10.60	$ 11.84	$ 5.02
Cash proceeds from the exercise of options	$ 300	$ 3,100	$ 2,800
Tax benefit recognized from stock option exercises	100	200	100
Total intrinsic value of options exercised	$ 477	3,800	2,900
Selling, General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 1,000	$ 500
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)	86,516	85,393	152,510
Fair value assumptions, exercise price (in dollars per share)	$ 24.55	$ 24.29	$ 11.39
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 1,800	$ 2,100	$ 2,600
TSR Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock units issued (in shares)	55,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value		$ 1,200
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%
Threshold performance, percentage	35.00%	35.00%	35.00%
ROIC Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Decrease in share-based compensation expense from change in vesting	$ (800)	$ (400)
Stock units issued (in shares)	55,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value		$ 900
Options awards vested	0
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%
Threshold performance, percentage	15.50%	15.00%	15.50%
Officers and Key Employees \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards granted vesting period	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
Adjustment \| ROIC Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividends accrued for performance share units	$ 100

Increase (Decrease) in Allocated Share-based Compensation Expense Due to Change in Vesting

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Share based compensation arrangement by share based payment award based on threshold performance achievement percentage.

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Share based compensation arrangement by share based payment award maximum number of shares available.

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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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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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 unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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The aggregate cash inflow comprised of the amount received from (a) employees to acquire the entity's shares under incentive awards, including stock option exercises and restricted stock arrangements, and (b) the excess tax benefit arising from such transactions.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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