Benefit Plans - Fair Values of Defined Benefit Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 29, 2012	Dec. 31, 2011
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	$ 270,181	$ 248,950
Equity Securities [Member] \| Large Cap Disciplined [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	95,970	90,237
Equity Securities [Member] \| Small/ Mid Cap [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	26,197	24,850
Equity Securities [Member] \| Intl/ World Equity [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	62,098	58,280
Debt Securities [Member] \| High Yield Bond Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	41,484	38,212
Debt Securities [Member] \| Emerging Markets Debt [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	13,350	12,517
Debt Securities [Member] \| Cash [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	2
Alternatives [Member] \| Structured Credit [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	31,080	24,854
Quoted Prices in Active Market for Identical Assets Level 1 [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	239,101	224,096
Quoted Prices in Active Market for Identical Assets Level 1 [Member] \| Equity Securities [Member] \| Large Cap Disciplined [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	95,970	90,237
Quoted Prices in Active Market for Identical Assets Level 1 [Member] \| Equity Securities [Member] \| Small/ Mid Cap [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	26,197	24,850
Quoted Prices in Active Market for Identical Assets Level 1 [Member] \| Equity Securities [Member] \| Intl/ World Equity [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	62,098	58,280
Quoted Prices in Active Market for Identical Assets Level 1 [Member] \| Debt Securities [Member] \| High Yield Bond Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	41,484	38,212
Quoted Prices in Active Market for Identical Assets Level 1 [Member] \| Debt Securities [Member] \| Emerging Markets Debt [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	13,350	12,517
Quoted Prices in Active Market for Identical Assets Level 1 [Member] \| Debt Securities [Member] \| Cash [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	2
Quoted Prices in Active Market for Identical Assets Level 1 [Member] \| Alternatives [Member] \| Structured Credit [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Other Observable Input Level 2 [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Other Observable Input Level 2 [Member] \| Equity Securities [Member] \| Large Cap Disciplined [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Other Observable Input Level 2 [Member] \| Equity Securities [Member] \| Small/ Mid Cap [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Other Observable Input Level 2 [Member] \| Equity Securities [Member] \| Intl/ World Equity [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Other Observable Input Level 2 [Member] \| Debt Securities [Member] \| High Yield Bond Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Other Observable Input Level 2 [Member] \| Debt Securities [Member] \| Emerging Markets Debt [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Other Observable Input Level 2 [Member] \| Debt Securities [Member] \| Cash [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Other Observable Input Level 2 [Member] \| Alternatives [Member] \| Structured Credit [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Unobservable Inputs Level 3 [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	31,080	24,854
Significant Unobservable Inputs Level 3 [Member] \| Equity Securities [Member] \| Large Cap Disciplined [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Unobservable Inputs Level 3 [Member] \| Equity Securities [Member] \| Small/ Mid Cap [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Unobservable Inputs Level 3 [Member] \| Equity Securities [Member] \| Intl/ World Equity [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Unobservable Inputs Level 3 [Member] \| Debt Securities [Member] \| High Yield Bond Fund [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Unobservable Inputs Level 3 [Member] \| Debt Securities [Member] \| Emerging Markets Debt [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Unobservable Inputs Level 3 [Member] \| Debt Securities [Member] \| Cash [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets
Significant Unobservable Inputs Level 3 [Member] \| Alternatives [Member] \| Structured Credit [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair values of the defined benefit assets	$ 31,080	$ 24,854

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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