Derivative Financial Instruments (Details 2) (USD $)	3 Months Ended	9 Months Ended
Oct. 01, 2011	Oct. 02, 2010	Oct. 01, 2011	Oct. 02, 2010
Derivative Instruments, Gain (Loss)
Reclassification of interest rate swap losses included in accumulated other comprehensive loss into earnings in the next 12 months	$ 1,800,000		$ 1,800,000
Minimum unencumbered cash and highly rated short-term investments required to be maintained all times under interest rate swap agreement	150,000,000		150,000,000
Cash flow hedges \| Interest rate swap
Derivative Instruments, Gain (Loss)
Loss Recognized in OCI on Derivatives (Effective Portion) during period	(66,000)	(835,000)	(492,000)	(2,734,000)
Loss Reclassified from Accumulated OCI into Income (Effective Portion), included in rent expense during period	$ (481,000)	$ (791,000)	$ (1,777,000)	$ (2,480,000)

This element represents the minimum unencumbered cash and highly rated short-term investments required to be maintained at any point of time under interest rate swap agreement. In case it falls below the minimum amount mentioned above, then the entity is required to post collateral with the counterparty in the amount of the fair value of the interest rate swap agreement in net liability positions.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The amount of net gains or losses on interest rate cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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