Summary of Derivative Financial Instruments Related Fair Value and Balance Sheet Classification (Detail) | 3-May-14 | 4-May-13 | 3-May-14 | 4-May-13 | 3-May-14 | 4-May-13 | 4-May-13 | 4-May-13 | 4-May-13 | 4-May-13 | 4-May-13 | 4-May-13 | 4-May-13 | 4-May-13 | 3-May-14 | 3-May-14 | 4-May-13 | 4-May-13 | 4-May-13 | 4-May-13 | 3-May-14 | 3-May-14 | 3-May-14 | 3-May-14 | 3-May-14 | 3-May-14 | 3-May-14 | 3-May-14 | 4-May-13 | 4-May-13 | 4-May-13 | 3-May-14 | 3-May-14 | 4-May-13 | 4-May-13 | 4-May-13 | 3-May-14 | 3-May-14 | 3-May-14 | 3-May-14 | 4-May-13 | 4-May-13 | 3-May-14 | 3-May-14 | 3-May-14 | 4-May-13 | 4-May-13 | 3-May-14 | 3-May-14 | 4-May-13 | 4-May-13 | 3-May-14 | 3-May-14 | 3-May-14 | 4-May-13 | 4-May-13 | 4-May-13 |
In Thousands, unless otherwise specified | USD ($) | USD ($) | Diesel Fuel Contracts | Diesel Fuel Contracts | Diesel Fuel Contracts | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Intercompany Balances, Primarily Short-Term Debt And Related Interest | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments | Merchandise Purchase Commitments |
| | | | USD ($) | Prepaid Expense | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense | Prepaid Expense | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense / (Accrued Expense) | Prepaid Expense | Prepaid Expense | Prepaid Expense |
| | | | | USD ($) | Conversion Of Zloty To Canadian Dollar | Conversion Of Zloty To Canadian Dollar | Conversion Of Zloty To Canadian Dollar | Conversion Of Pound To Canadian Dollar | Conversion Of Pound To Canadian Dollar | Conversion Of Pound To Canadian Dollar | Conversion Of Euro To Pound | Conversion Of Euro To Pound | Conversion Of Euro To Pound | Conversion Of Euro To US Dollar | Conversion Of Euro To US Dollar | Conversion Of Euro To US Dollar | Conversion Of Euro To US Dollar | Conversion Of US Dollar To Pound | Conversion Of US Dollar To Pound | Conversion Of Zloty To Canadian Dollar | Conversion Of Zloty To Canadian Dollar | Conversion Of Zloty To Canadian Dollar | Conversion Of Euro To Pound | Conversion Of Euro To Pound | Conversion Of Euro To Pound | Conversion Of US Dollar To Pound | Conversion Of US Dollar To Pound | Conversion Of Canadian Dollar To Euro | Conversion Of Canadian Dollar To Euro | Conversion Of Canadian Dollar To Euro | Conversion Of Pound To US Dollar | Conversion Of Pound To US Dollar | Conversion Of Pound To Euro | Conversion Of Pound To Euro | Conversion Of Pound To Euro | Conversion of Us Dollar to Yen | Conversion of Us Dollar to Yen | Conversion Of Canadian Dollar To US Dollar | Conversion Of Canadian Dollar To US Dollar | Conversion Of Canadian Dollar To US Dollar | Conversion Of Canadian Dollar To US Dollar | Conversion Of Canadian Dollar To Euro | Conversion Of Canadian Dollar To Euro | Conversion Of Canadian Dollar To Euro | Conversion Of Pound To US Dollar | Conversion Of Pound To US Dollar | Conversion Of US Dollar To Euro | Conversion Of US Dollar To Euro | Conversion Of US Dollar To Euro | Conversion Of US Dollar To Euro | Conversion Of Zloty To Pound | Conversion Of Zloty To Pound | Conversion Of Zloty To Pound | Conversion Of Pound To Zloty | Conversion Of Pound To Zloty | Conversion Of Pound To Zloty |
| | | | | | USD ($) | CAD | PLN | USD ($) | CAD | GBP (£) | USD ($) | EUR (€) | GBP (£) | USD ($) | EUR (€) | USD ($) | EUR (€) | USD ($) | GBP (£) | USD ($) | CAD | PLN | USD ($) | EUR (€) | GBP (£) | USD ($) | GBP (£) | USD ($) | CAD | EUR (€) | USD ($) | GBP (£) | USD ($) | EUR (€) | GBP (£) | USD ($) | JPY (¥) | USD ($) | CAD | USD ($) | CAD | USD ($) | CAD | EUR (€) | USD ($) | GBP (£) | USD ($) | EUR (€) | USD ($) | EUR (€) | USD ($) | GBP (£) | PLN | USD ($) | GBP (£) | PLN |
Derivatives, Fair Value [Line Items] | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Economic hedges for which hedge accounting was not elected, Diesel contracts, Pay | ' | ' | 'Fixed on 1.6M - 1.8M gal per month | 'Fixed on 1.5M - 1.7M gal per month | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Hedge accounting not elected, Pay | ' | ' | ' | ' | ' | ' | ' | 141,500 | ' | ' | £ 25,000 | ' | € 44,281 | ' | ' | € 44,850 | ' | € 90,292 | $87,117 | ' | ' | ' | 87,073 | ' | € 39,000 | ' | $90,309 | ' | ' | 8,149 | ' | ' | £ 145,258 | ' | ' | £ 4,289 | $844 | ' | ' | 411,075 | ' | 323,489 | ' | 15,483 | ' | ' | £ 111,217 | $23,376 | ' | $9,907 | ' | ' | ' | 128,099 | ' | £ 12,823 | ' |
Economic hedges for which hedge accounting was not elected, Diesel contracts, Receive | ' | ' | 'Float on 1.6M - 1.8M gal per month | 'Float on 1.5M - 1.7M gal per month | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' |
Hedge accounting not elected, Receive | ' | ' | ' | ' | ' | ' | 44,551 | ' | ' | 38,946 | ' | ' | ' | 35,781 | 61,842 | ' | 118,511 | ' | ' | 55,000 | ' | 30,585 | ' | ' | ' | 32,369 | ' | 55,000 | ' | ' | 6,100 | 236,200 | ' | ' | 5,000 | ' | ' | 5,138 | 374,675 | ' | 319,678 | ' | ' | ' | 10,200 | 171,000 | ' | ' | 17,001 | ' | 7,580 | ' | 25,079 | ' | ' | ' | 62,813 |
Blended Contract Rate | ' | ' | ' | ' | ' | 0.3148 | 0.3148 | 0.3148 | 1.5578 | 1.5578 | 1.5578 | 0.808 | 0.808 | 0.808 | 1.3789 | 1.3789 | 1.3125 | 1.3125 | 0.6313 | 0.6313 | 0.3513 | 0.3513 | 0.3513 | 0.83 | 0.83 | 0.83 | 0.609 | 0.609 | 0.7486 | 0.7486 | 0.7486 | 1.6261 | 1.6261 | 1.1658 | 1.1658 | 1.1658 | 6.0877 | 6.0877 | 0.9115 | 0.9115 | 0.9882 | 0.9882 | 0.6588 | 0.6588 | 0.6588 | 1.5375 | 1.5375 | 0.7273 | 0.7273 | 0.7651 | 0.7651 | 0.1958 | 0.1958 | 0.1958 | 4.8985 | 4.8985 | 4.8985 |
Current Asset | 7,662 | 2,910 | ' | ' | 1,001 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 26 | ' | ' | 513 | ' | ' | 2,248 | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | ' | 3,346 | ' | 1,954 | ' | 56 | ' | ' | 717 | ' | 207 | ' | 71 | ' | 265 | ' | ' | 168 | ' | ' |
Current (Liability) | -12,463 | -11,595 | ' | -427 | ' | -604 | ' | ' | -475 | ' | ' | -2,537 | ' | ' | -350 | ' | -111 | ' | -1,572 | ' | -651 | ' | ' | -49 | ' | ' | ' | ' | -79 | ' | ' | -8,698 | ' | -123 | ' | ' | -24 | ' | -2,621 | ' | -2,757 | ' | -8 | ' | ' | -2,875 | ' | -8 | ' | -35 | ' | -54 | ' | ' | ' | ' | ' |
Net Fair Value | ($4,801) | ($8,685) | ' | ($427) | $1,001 | ($604) | ' | ' | ($475) | ' | ' | ($2,537) | ' | ' | ($350) | ' | ($111) | ' | ($1,572) | ' | ($625) | ' | ' | $464 | ' | ' | $2,248 | ' | ($79) | ' | ' | ($8,698) | ' | ($123) | ' | ' | ($24) | ' | $725 | ' | ($803) | ' | $48 | ' | ' | ($2,158) | ' | $199 | ' | $36 | ' | $211 | ' | ' | $168 | ' | ' |