Schedule of Inventories (Detail) - USD ($) $ in Thousands |
Sep. 30, 2016 |
Mar. 31, 2016 |
|---|---|---|
| Inventory [Line Items] | ||
| Inventories | $ 217,582 | $ 243,595 |
| Raw Materials and Material-in-Progress [Member] | ||
| Inventory [Line Items] | ||
| Inventories | 104,759 | 119,060 |
| Finished Cement [Member] | ||
| Inventory [Line Items] | ||
| Inventories | 17,096 | 21,834 |
| Gypsum Wallboard [Member] | ||
| Inventory [Line Items] | ||
| Inventories | 5,939 | 5,839 |
| Frac Sand [Member] | ||
| Inventory [Line Items] | ||
| Inventories | 3,375 | 5,501 |
| Aggregates [Member] | ||
| Inventory [Line Items] | ||
| Inventories | 8,387 | 10,660 |
| Paperboard [Member] | ||
| Inventory [Line Items] | ||
| Inventories | 3,647 | 7,575 |
| Repair Parts and Supplies [Member] | ||
| Inventory [Line Items] | ||
| Inventories | 68,777 | 68,155 |
| Fuel and Coal [Member] | ||
| Inventory [Line Items] | ||
| Inventories | $ 5,602 | $ 4,971 |