Pension Benefits (Components Of Net Periodic Benefit Cost) (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 25, 2011	Sep. 26, 2010	Sep. 25, 2011	Sep. 26, 2010	Dec. 25, 2011
Pension Benefits
Service cost	$ 247,000	$ 207,000	$ 736,000	$ 636,000
Interest cost	1,125,000	1,047,000	3,346,000	3,222,000
Expected return on plan assets	39,000	(15,000)	117,000	(45,000)
Amortization of actuarial loss (gain)	12,000	(6,000)	37,000	(18,000)
Amortization of transition obligation	33,000	30,000	98,000	92,000
Amortization of prior service costs	1,000	1,000	2,000	2,000
Net periodic pension cost	1,457,000	1,264,000	4,336,000	3,889,000
Estimated employer contributions					4,900,000
Pension contributions			$ 3,800,000

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The amount of gains or losses recognized in net periodic benefit cost.

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The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

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The amount of the transition obligation or asset recognized in net periodic benefit cost.

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The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan in the current remaining fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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The amount of cash or cash equivalents contributed during the reporting period by the entity to fund its pension plans and its non-pension postretirement benefit plans.

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