The realized income tax benefit.

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The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

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No definition available.

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

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Unrecognized cost of unvested share-based compensation awards.

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

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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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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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No definition available.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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No definition available.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Gross number of share options (or share units) granted during the period.

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No definition available.

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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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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

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Number of share options (or share units) exercised during the current period.

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Equity Compensation Plans - Narrative (Detail) - USD ($)		12 Months Ended
	Apr. 27, 2012	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense		$ 4,300,000	$ 4,400,000	$ 2,800,000
Compensation costs capitalized as part of inventory		0	0	0
Tax benefit from compensation expense		$ 4,000,000	$ 1,900,000	$ 1,500,000
Options granted (in shares)		99,840	56,580	91,900
Weighted-average grant-date fair value of options (in dollars per share)		$ 17.91	$ 21.11	$ 15.28
Options exercised (in shares)		90,897	76,333	166,175
Total intrinsic value for options exercised		$ 3,600,000	$ 2,400,000	$ 3,500,000
Cash received from exercise of stock option		1,300,000	1,200,000	1,500,000
Fair value of restrictions lapsed		$ 8,000,000	3,400,000	1,400,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, term		10 years
Realized income tax benefit		$ 1,100,000	$ 700,000	$ 1,100,000
Total unrecognized compensation cost		$ 3,400,000
Weighted average expected amortization period		3 years 1 month
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period		3 years
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period		4 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value of options (in dollars per share)		$ 45.18	$ 49.70	$ 34.09
Total unrecognized compensation cost		$ 5,900,000
Weighted average expected amortization period		2 years 3 months 24 days
Granted (in shares)		76,000
Restricted stock forfeited (in shares)		14,045	33,800	147,187
Shares paid for tax withholding for share based compensation (in shares)		42,288
Shares paid for tax withholding for share based compensation, value of shares withheld		$ 2,800,000
Time Based Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		22,700	31,455	33,755
Time Based Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period		2 years
Time Based Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period		4 years
Performance Based Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		52,595	44,423	38,170
Time-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		485	8,570
2012 Stock Repurchase Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options and restricted shares authorized (in shares)	1,750,000
Number of additional shares authorized (in shares)	1,200,000