Fair Value Measurement - Summary of Assets and Liabilities Carried at Fair Value (Detail) (USD $) | Jun. 30, 2014 | Mar. 31, 2014 |
In Thousands, unless otherwise specified |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Deferred compensation - unearned ESOP shares | ($233,106) | ($197,888) |
Level 3 [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Total liabilities & mezzanine equity at fair value on a recurring basis | 777,499 | 645,227 |
Interest rate swaps [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Derivative assets - diesel fuel contracts | ' | ' |
Derivative liability - interest rate swaps | 1,103 | 1,001 |
Fair Value, Measurements, Recurring [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Total Assets at fair value on a recurring basis | 33 | 27 |
Contingent consideration for acquisitions | 2,276 | 2,276 |
Redeemable Common Stock | 659,431 | 549,119 |
Redeemable Convertible Preferred Stock | 348,898 | 291,720 |
Deferred compensation - unearned ESOP shares | -233,106 | -197,888 |
Total liabilities & mezzanine equity at fair value on a recurring basis | 778,602 | 646,228 |
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Total Assets at fair value on a recurring basis | ' | ' |
Contingent consideration for acquisitions | ' | ' |
Redeemable Common Stock | ' | ' |
Redeemable Convertible Preferred Stock | ' | ' |
Deferred compensation - unearned ESOP shares | ' | ' |
Total liabilities & mezzanine equity at fair value on a recurring basis | ' | ' |
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Total Assets at fair value on a recurring basis | 33 | 27 |
Contingent consideration for acquisitions | ' | ' |
Redeemable Common Stock | ' | ' |
Redeemable Convertible Preferred Stock | ' | ' |
Deferred compensation - unearned ESOP shares | ' | ' |
Total liabilities & mezzanine equity at fair value on a recurring basis | 1,103 | 1,001 |
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Total Assets at fair value on a recurring basis | ' | ' |
Contingent consideration for acquisitions | 2,276 | 2,276 |
Redeemable Common Stock | 659,431 | 549,119 |
Redeemable Convertible Preferred Stock | 348,898 | 291,720 |
Deferred compensation - unearned ESOP shares | -233,106 | -197,888 |
Total liabilities & mezzanine equity at fair value on a recurring basis | 777,499 | 645,227 |
Fair Value, Measurements, Recurring [Member] | Diesel Fuel Contracts [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Derivative assets - diesel fuel contracts | 33 | 27 |
Fair Value, Measurements, Recurring [Member] | Diesel Fuel Contracts [Member] | Level 1 [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Derivative assets - diesel fuel contracts | ' | ' |
Fair Value, Measurements, Recurring [Member] | Diesel Fuel Contracts [Member] | Level 2 [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Derivative assets - diesel fuel contracts | 33 | 27 |
Fair Value, Measurements, Recurring [Member] | Diesel Fuel Contracts [Member] | Level 3 [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Derivative assets - diesel fuel contracts | ' | ' |
Fair Value, Measurements, Recurring [Member] | Interest rate swaps [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Derivative liability - interest rate swaps | 1,103 | 1,001 |
Fair Value, Measurements, Recurring [Member] | Interest rate swaps [Member] | Level 1 [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Derivative liability - interest rate swaps | ' | ' |
Fair Value, Measurements, Recurring [Member] | Interest rate swaps [Member] | Level 2 [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Derivative liability - interest rate swaps | 1,103 | 1,001 |
Fair Value, Measurements, Recurring [Member] | Interest rate swaps [Member] | Level 3 [Member] | ' | ' |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ' | ' |
Derivative liability - interest rate swaps | ' | ' |