Pension and Other Post-retirement Benefits (Detail) - Actuarial present value (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 29, 2012	Dec. 31, 2011	Jan. 01, 2011
Funded Status
Actuarial gain (loss)	$ 800	$ 1,600	$ 1,400
Pension Plans, Defined Benefit [Member]
Funded Status
Beginning of year	(48,570)	(43,125)
Interest cost	(2,043)	(2,121)	(2,211)
Actuarial gain (loss)	(4,057)	(6,843)
Benefits paid	3,457	3,519
Accumulated benefit obligation	(51,213)	(48,570)	(43,125)
Fair value of plan assets
Beginning of year	32,895	29,762
Actual return on plan assets	3,471	576
Employer contributions	3,092	6,076
Benefits paid	(3,457)	(3,519)
End of year	36,001	32,895	29,762
Funded status	(15,212)	(15,675)
Other Postretirement Benefit Plans, Defined Benefit [Member]
Funded Status
Beginning of year	(721)	(744)
Interest cost	(29)	(35)
Participant contributions	(15)	(36)
Actuarial gain (loss)	135	67
Benefits paid	74	27
Accumulated benefit obligation	(556)	(721)
Fair value of plan assets
Employer contributions	59	(9)
Participant contributions	15	36
Benefits paid	(74)	(27)
Funded status	$ (556)	$ (721)

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- Definition

The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

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- Definition

Amount of gain (loss) from a decision to temporarily deviate from the substantive plan, or from a change in benefit obligation or plan asset value from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover or salary scale.

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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-Glossary Accumulated Postretirement Benefit Obligation

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- Definition

The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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-Glossary Postretirement Benefits

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

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The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets.

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Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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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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