Stock Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 3,704	$ 2,595	$ 2,239
Compensation expense related with stock options	915	1,274	1,437
Compensation expense for stock awards	$ 2,396	$ 1,321	$ 802
Maximum number of shares authorized to issued as options	827,476
Term life of options	10 years
Vesting period of stock issue	3 years	3 years	3 years
Number of options granted	55,000	108,620	353,600
Weighted average grant date fair value of the options granted	$ 12.61	$ 9.48	$ 5.17
Unrecognized compensation costs to be recognized for stock options	$ 600
Unrecognized compensation costs to be recognized for restricted stocks	$ 1,100
Unrecognized compensation costs, period for recognition	2 years
Cash proceeds from the exercise of options	$ 2,041	$ 1,671	$ 4,013
Total intrinsic value of options exercised	$ 2,600	$ 2,000	$ 1,400
Common stock issued	114,475	114,300	94,800
Weighted average grant date fair value Per Share of the Stock Award	$ 23.72
Unrecognized share-based compensation expense	$ 1,500
Unrecognized compensation expense expected to be recognized	2 years
Performance Based Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 400
TSR Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options granted	35,775
Weighted average grant date fair value of the options granted	$ 28.61
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 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options granted	35,775
Weighted average grant date fair value of the options granted	$ 25.16
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%
Key Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock issue	3 years
Non-employee Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock issue	1 year
Selling, General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 3,700	$ 2,600	$ 2,200

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Share based compensation arrangement by share based payment award per share weighted average grant date fair value.

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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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Unrecognized share based compensation expense expected to be recognized period.

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Unrecognized share based compensation expenses.

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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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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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Unrecognized cost of unvested options awarded to employees as compensation.

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The total cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards, including stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

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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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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 share instruments newly issued under a share-based compensation plan.

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- Definition

The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

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