Stock-Based Compensation (Details) (USD $)	9 Months Ended
Sep. 29, 2012	Sep. 29, 2012
Summary of stock option activity
Balance, Shares at December 31, 2011	692,800
Balance, Weighted Average Price at December 31, 2011	$ 5.46
Granted, Shares	20,000
Granted, Weighted Average Price	$ 22.71
Exercised, Shares	(344,100)
Exercised, Weighted Average Price	$ 4.22
Balance, Shares at September 29, 2012	368,700
Balance, Weighted Average Price at September 29, 2012	$ 7.55
Balance, Weighted Average Remaining Term (In years) at September 29, 2012	4 years 7 months 6 days
Balance, Aggregate Intrinsic Value at September 29, 2012	$ 8,835,000
Options exercisable, Shares at September 29, 2012	228,700
Options exercisable, Weighted Average Price at September 29, 2012		$ 5.32
Options exercisable, Weighted Average Remaining Term (In years) at September 29, 2012	3 years 2 months 12 days
Options exercisable, Aggregate Intrinsic Value at September 29, 2012	$ 5,990,000

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Gross 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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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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