Stockholders' Equity - Summary of Restricted Stock Activity (Detail) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Income tax benefit	$ (54,000)	$ (164,000)	$ (444,000)
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unvested restricted stock outstanding at beginning of year	1,189,473
Granted, Shares	369,350	469,465	850,771
Vested, Shares	(806,927)
Cancelled or forfeited, Shares	(12,431)
Unvested restricted stock outstanding at end of year	739,465	1,189,473
Unvested restricted stock outstanding at beginning period, weighted-average grand date fair value	$ 7.51
Weighted-average fair value per restricted stock granted during year	5.47	$ 9.11	$ 7.82
Vested, weighted-average grant date fair value	9.11
Cancelled or forfeited, weighted-average grant date fair value	6.20
Unvested restricted stock outstanding at end of year, Weighted-average granted date fair value	$ 7.79	$ 7.51
Total fair value of restricted stock granted	$ 2,019,000	$ 4,277,000	$ 6,652,000
Income tax benefit	$ (398,000)	$ (1,659,000)	$ (1,157,000)
Total weighted-average remaining vesting period in years	1 year 9 months 10 days	1 year 11 months 12 days	2 years 4 months 28 days
Total fair value of restricted stock vested during the year	$ 7,355,000	$ 3,124,000	$ 2,579,000
Restricted Stock [Member] \| Cost of Sales [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	385,000	312,000	240,000
Restricted Stock [Member] \| SG&A [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 7,574,000	$ 3,987,000	$ 2,773,000
Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unvested restricted stock outstanding at beginning of year	43,764
Granted, Shares	35,511	37,992	27,654
Vested, Shares	(10,941)
Unvested restricted stock outstanding at end of year	68,334	43,764
Unvested restricted stock outstanding at beginning period, weighted-average grand date fair value	$ 11.42
Weighted-average fair value per restricted stock granted during year	5.28	$ 9.87	$ 13.56
Vested, weighted-average grant date fair value	11.42
Unvested restricted stock outstanding at end of year, Weighted-average granted date fair value	$ 8.23	$ 11.42
Total fair value of restricted stock granted	$ 187,000	$ 375,000	$ 375,000
Income tax benefit	$ (34,000)	$ (115,000)	$ (144,000)
Total weighted-average remaining vesting period in years	1 year 9 months	3 years 18 days	2 years 6 months
Total fair value of restricted stock vested during the year	$ 125,000	$ 250,000
Restricted Stock Units [Member] \| SG&A [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 187,000	$ 375,000	$ 375,000

Weighted average remaining vesting period in years.

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Share-based compensation arrangement by share based payment award restricted stock vested in period fair value.

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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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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 number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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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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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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