Stock-Based Compensation (Stock Option Activity Under The Principal Option Plans) (Details) (Stock Options And Awards, USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended
Dec. 28, 2014	Mar. 29, 2015
Stock Options And Awards
Number of Options Outstanding (in shares)
Number of shares, outstanding at beginning of period (shares)		2,349,447
Number of shares, granted (shares)		252,260
Number of shares, exercised (shares)		(11,005)
Number of shares, forfeited or expired (shares)		(85,803)
Number of shares, outstanding at end of period (shares)	2,349,447	2,504,899
Number of shares, vested and expected to vest (shares)		2,380,156
Number of shares, exercisable (shares)		1,992,965
Weighted average exercise price
Weighted-average exercise price, outstanding at beginning of period (USD per share)		$ 17.77
Weighted-average exercise price, granted (USD per share)		$ 13.56
Weighted-average exercise price, exercised (USD per share)		$ 9.46
Weighted-average exercise price, forfeited or expired (USD per share)		$ 17.03
Weighted-average exercise price, outstanding at end of period (USD per share)	$ 17.77	$ 17.41
Weighted-average exercise price, vested and expected to vest (USD per share)		$ 17.61
Weighted-average exercise price, exercisable (USD per share)		$ 18.57
Additional Disclosures [Abstract]
Weighted-average remaining contractual term, outstanding at beginning of period in years	3 years 11 months 23 days	4 years 5 months 20 days
Weighted-average remaining contractual term, outstanding at end of period in years	3 years 11 months 23 days	4 years 5 months 20 days
Weighted-average remaining contractual term, vested and expected to vest in years		4 years 2 months 16 days
Weighted-average remaining contractual term, exercisable		3 years 3 months 12 days
Aggregate intrinsic value, outstanding at beginning of period		$ 2,716
Aggregate intrinsic value, outstanding at end of period	2,716	936
Aggregate intrinsic value, vested and expected to vest		922
Aggregate intrinsic value, exercisable		$ 692

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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