Employee service share based compensation recognized period costs capitalized amount.

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Estimated forfeiture rate for unvested options for all non-senior management.

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Estimated forfeiture rate for unvested options for senior management.

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Number of groups within the employee population.

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Number of stock option plans.

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Percentage of stock options granted to all other employees expected to vest.

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Percentage of stock options granted to senior management expected to vest.

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- Definition

Reduction in compensation expense due to revised estimated forfeiture rates.

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- Definition

Shares based compensation arrangement by shares based payment award options exercisable intrinsic value.

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Stock-Based Compensation Expense.

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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.

+ References

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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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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- Definition

The date when the equity-based award expires as specified in the award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

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Description of the period of time over 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, which may be expressed in a variety of ways (for example, in years, month and year).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

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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-Publisher FASB
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Stock-Based Compensation Expense (Details Textual) (USD $)	3 Months Ended			6 Months Ended
	Jul. 03, 2011	Apr. 03, 2011	Jul. 04, 2010	Jul. 03, 2011	Jul. 04, 2010	Dec. 31, 2010
Stock-Based Compensation Expense (Textuals) [Abstract]
Shares available for grant under stock option plans	7,063,000			7,063,000
Number of stock option plans	2			2
Weighted-average grant-date fair values of stock options granted	$ 11.95		$ 6.89	$ 11.77	$ 7.10
Number of groups within the employee population	2			2
Percentage of stock options granted to senior management expected to vest	66.00%			66.00%
Percentage of stock options granted to all other employees expected to vest	68.00%			68.00%
Reduction in compensation expense due to revised estimated forfeiture rates		$ 80,000
Estimated forfeiture rate for unvested options for senior management	13.00%			13.00%
Estimated forfeiture rate for unvested options for all non-senior management	14.00%			14.00%
Total stock-based compensation expense	1,957,000		427,000	4,309,000	394,000
Income tax benefit recognized related to stock-based compensation expense	654,000		143,000	1,445,000	124,000
Compensation expense capitalized	0			0		0
Total intrinsic values of stock options exercised	7,969,000		38,000	12,637,000	51,000
Total unrecognized compensation expense related to non-vested stock options	$ 9,939,000			$ 9,939,000
Weighted-average period for unrecognized compensation expense related to non-vested stock options (years)	1.9
General Stock Option Plan [Member]
Stock-Based Compensation Expense (Textuals) [Abstract]
Shares available for grant under stock option plans	5,570,640			5,570,640
Expiration period of stock option plans				10 years
Vesting period for stock option plans				4 years
Stock Option and Incentive Plan [Member]
Stock-Based Compensation Expense (Textuals) [Abstract]
Shares available for grant under stock option plans	1,492,360			1,492,360
Expiration period of stock option plans				10 years
Vesting period for stock option plans				4 years