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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Reduction in compensation expense due to revised estimated forfeiture rates.

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Share based compensation arrangement by share based payment award options vested fair value.

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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.

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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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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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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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Stock-Based Compensation Expense (Details Textual) (USD $)	3 Months Ended			9 Months Ended
	Oct. 02, 2011 Years Year EmployeeGroup BusinessSegment OptionPlan	Apr. 03, 2011	Oct. 03, 2010	Oct. 02, 2011 Year Years EmployeeGroup BusinessSegment OptionPlan	Oct. 03, 2010	Dec. 31, 2010
Stock-Based Compensation Expense (Textual) [Abstract]
Shares available for grant under stock option plans	7,013,112			7,013,112
Number of stock option plans	2			2
Weighted-average grant-date fair values of stock options granted	$ 11.89		$ 6.89	$ 11.78	$ 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	1,520,000		1,278,000	5,829,000	1,672,000
Income tax benefit recognized related to stock-based compensation expense	502,000		421,000	1,947,000	552,000
Compensation expense capitalized	0			0		0
Total intrinsic values of stock options exercised	5,254,000		2,004,000	17,808,000	2,055,000
Total unrecognized compensation expense related to non-vested stock options	8,789,000			8,789,000
Weighted-average period for unrecognized compensation expense related to non-vested stock options (years)	1.6
Total fair values of stock options vested	$ 469,000		$ 557,000	$ 9,846,000	$ 12,790,000
General Stock Option Plan [Member]
Stock-Based Compensation Expense (Textual) [Abstract]
Shares available for grant under stock option plans	5,519,627			5,519,627
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 (Textual) [Abstract]
Shares available for grant under stock option plans	1,493,485			1,493,485
Expiration period of stock option plans				10 years
Vesting period for stock option plans				4 years