Investments In Unconsolidated Entities (Summarized Balance Sheet Financial Information of Investments in Unconsolidated Affiliates) (Detail) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2013	Apr. 30, 2012
Schedule of Equity Method Investments [Line Items]
Current assets	$ 15,470	$ 17,513
Noncurrent assets	30,246	34,597
Current liabilities	14,406	12,815
Noncurrent liabilities	$ 5,126	$ 5,382

The amount of current assets reported by an equity method investment of the entity.

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+ Details

- Definition

The amount of current liabilities reported by an equity method investment of the entity.

+ References

+ Details

- Definition

The amount of noncurrent assets reported by an equity method investment of the entity.

+ References

+ Details

- Definition

The amount of noncurrent liabilities reported by an equity method investment of the entity.

+ References

+ Details