Share-Based Compensation (Details 5) (USD $)	12 Months Ended
Jan. 03, 2015	Dec. 28, 2013
Options Outstanding
Number Outstanding (in shares)	1,154,945
Weighted-Average Remaining Contractual Life	3 years 8 months 23 days
Weighted-Average Exercise Price (in dollars per share)	$ 29.93
Options Exercisable
Number Exercisable (in shares)	737,760
Weighted-Average Exercise Price (in dollars per share)	$ 33.14
Non-vested Options, Number of Shares
Balance at the beginning of the period (in shares)	401,678
Granted (in shares)	178,608
Vested (in shares)	(153,126)
Forfeited (in shares)	(9,975)
Balance at the end of the period (in shares)	417,185
Non-vested Options, Weighted-Average Fair Value
Balance at the beginning of the period (in dollars per share)	$ 8.16
Granted (in dollars per share)	$ 12.24
Vested (in dollars per share)	$ 9.03
Forfeited (in dollars per share)	$ 8.30
Balance at the end of the period (in dollars per share)	$ 9.98
$18.48
Options Outstanding
Number Outstanding (in shares)	254,355
Weighted-Average Remaining Contractual Life	5 years 10 months 17 days
Weighted-Average Exercise Price (in dollars per share)	$ 18.48	$ 18.48
Options Exercisable
Number Exercisable (in shares)	63,578
Weighted-Average Exercise Price (in dollars per share)	$ 18.48
$18.49 - 22.81
Share-based compensation
Exercise price, low end of range (in dollars per share)	$ 18.49
Exercise price, high end of range (in dollars per share)	$ 22.81
Options Outstanding
Number Outstanding (in shares)	328,253
Weighted-Average Remaining Contractual Life	3 years 4 months 21 days
Weighted-Average Exercise Price (in dollars per share)	$ 21.68
Options Exercisable
Number Exercisable (in shares)	284,453
Weighted-Average Exercise Price (in dollars per share)	$ 21.64
$22.82 - 29.07
Share-based compensation
Exercise price, low end of range (in dollars per share)	$ 22.82
Exercise price, high end of range (in dollars per share)	$ 29.07
Options Outstanding
Number Outstanding (in shares)	86,665
Weighted-Average Remaining Contractual Life	2 years
Weighted-Average Exercise Price (in dollars per share)	$ 24.22
Options Exercisable
Number Exercisable (in shares)	82,665
Weighted-Average Exercise Price (in dollars per share)	$ 24.18
$29.08 - 32.26
Share-based compensation
Exercise price, low end of range (in dollars per share)	$ 29.08
Exercise price, high end of range (in dollars per share)	$ 32.26
Options Outstanding
Number Outstanding (in shares)	178,608
Weighted-Average Remaining Contractual Life	6 years 11 months 5 days
Weighted-Average Exercise Price (in dollars per share)	$ 30.97
$32.27 - 48.85
Share-based compensation
Exercise price, low end of range (in dollars per share)	$ 32.27
Exercise price, high end of range (in dollars per share)	$ 48.85
Options Outstanding
Number Outstanding (in shares)	42,500
Weighted-Average Remaining Contractual Life	9 months 15 days
Weighted-Average Exercise Price (in dollars per share)	$ 42.58
Options Exercisable
Number Exercisable (in shares)	42,500
Weighted-Average Exercise Price (in dollars per share)	$ 42.58
$48.86 - 50.00
Share-based compensation
Exercise price, low end of range (in dollars per share)	$ 48.86
Exercise price, high end of range (in dollars per share)	$ 50.00
Options Outstanding
Number Outstanding (in shares)	150,000
Weighted-Average Remaining Contractual Life	1 year 6 months
Weighted-Average Exercise Price (in dollars per share)	$ 50.00
Options Exercisable
Number Exercisable (in shares)	150,000
Weighted-Average Exercise Price (in dollars per share)	$ 50.00
$50.01 - 53.72
Share-based compensation
Exercise price, low end of range (in dollars per share)	$ 50.01
Exercise price, high end of range (in dollars per share)	$ 53.72
Options Outstanding
Number Outstanding (in shares)	114,564
Weighted-Average Remaining Contractual Life	3 months
Weighted-Average Exercise Price (in dollars per share)	$ 50.73
Options Exercisable
Number Exercisable (in shares)	114,564
Weighted-Average Exercise Price (in dollars per share)	$ 50.73

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Net 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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Number of non-vested options forfeited.

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Weighted average grant-date fair value of non-vested options forfeited.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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