| Derivative and Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified | 4 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
| Dec. 14, 2012
 Amended credit facility | Apr. 21, 2013
 Variable-to-fixed interest rate swap agreement
 Rabobank
 item | Dec. 30, 2012
 Variable-to-fixed interest rate swap agreement
 Rabobank | Dec. 25, 2011
 Variable-to-fixed interest rate swap agreement
 Rabobank | Aug. 31, 2011
 Variable-to-fixed interest rate swap agreement
 Rabobank | |
| Derivative and other comprehensive income | |||||
| Number of derivative instruments held | 1 | ||||
| Notional amount of derivatives | $ 65.5 | $ 74.1 | |||
| Notional amount of derivatives expired | 4.7 | 0.9 | |||
| Estimated notional hedge amount on expiration date which is June 30, 2015 | 50.6 | ||||
| Amount of debt hedged | $ 225 | ||||
| Fixed rate of interest on derivative (as a percent) | 1.135% | ||||
| Reference rate for variable rate received on interest rate derivative | 3-month spot LIBOR | ||||
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- Definition Represents the monetary amount specified by the derivatives expired during the period. Expressed as an absolute value. No definition available. 
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- Definition Represents the estimated notional amount of a derivative instrument on the expiration date. No definition available. 
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- Definition Amount of the hedged item as of the balance sheet date related to the derivative. For example, the hedged balance on a debt instrument. No definition available. 
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- Definition The reference rate for the variable rate of the interest rate derivative, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR. No definition available. 
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- Definition Fixed interest rate related to the interest rate derivative. No definition available. 
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- Details 
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- Definition The number of derivative instruments of a particular group held by the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Aggregate notional amount of all derivatives designated as cash flow hedging instruments. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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