(Schedule of Ratio of Net Indebtedness) (Details)	9 Months Ended
	Sep. 07, 2012
Line Of Credit Facility Leverage Range [Line Items]
Percent of unused portion line of credit facility trigerring lower commitment fee (as a percent)	50.00%
Less than 4.00 to 1.00 [Member]
Summary of leverage and applicable margin
Line of credit facility applicable margin rate	2.25%
Greater than or equal to 4.00 to 1.00 but less than 5.00 to 1.00 [Member]
Summary of leverage and applicable margin
Line of credit facility applicable margin rate	2.50%
Greater than or equal to 5.00 to 1.00 but less than 5.50 to 1.00 [Member]
Summary of leverage and applicable margin
Line of credit facility applicable margin rate	2.75%
Greater than or equal to 5.50 to 1.00 but less than 6.00 to 1.00 [Member]
Summary of leverage and applicable margin
Line of credit facility applicable margin rate	3.00%
Greater than or equal to 6.00 to 1.00 [Member]
Summary of leverage and applicable margin
Line of credit facility applicable margin rate	3.25%
Minimum [Member]
Line Of Credit Facility Leverage Range [Line Items]
Line of credit facility, unused capacity, commitment fee (as a percent)	0.40%
Minimum [Member] | Greater than or equal to 4.00 to 1.00 but less than 5.00 to 1.00 [Member]
Summary of leverage and applicable margin
Ratio of net indebtedness to EBITDA (as a percent)	4
Minimum [Member] | Greater than or equal to 5.00 to 1.00 but less than 5.50 to 1.00 [Member]
Summary of leverage and applicable margin
Ratio of net indebtedness to EBITDA (as a percent)	5
Minimum [Member] | Greater than or equal to 5.50 to 1.00 but less than 6.00 to 1.00 [Member]
Summary of leverage and applicable margin
Ratio of net indebtedness to EBITDA (as a percent)	5.5
Minimum [Member] | Greater than or equal to 6.00 to 1.00 [Member]
Summary of leverage and applicable margin
Ratio of net indebtedness to EBITDA (as a percent)	6
Maximum [Member]
Line Of Credit Facility Leverage Range [Line Items]
Line of credit facility, unused capacity, commitment fee (as a percent)	0.30%
Maximum [Member] | Less than 4.00 to 1.00 [Member]
Summary of leverage and applicable margin
Ratio of net indebtedness to EBITDA (as a percent)	4
Maximum [Member] | Greater than or equal to 4.00 to 1.00 but less than 5.00 to 1.00 [Member]
Summary of leverage and applicable margin
Ratio of net indebtedness to EBITDA (as a percent)	5
Maximum [Member] | Greater than or equal to 5.00 to 1.00 but less than 5.50 to 1.00 [Member]
Summary of leverage and applicable margin
Ratio of net indebtedness to EBITDA (as a percent)	5.5
Maximum [Member] | Greater than or equal to 5.50 to 1.00 but less than 6.00 to 1.00 [Member]
Summary of leverage and applicable margin
Ratio of net indebtedness to EBITDA (as a percent)	6