Goodwill and Other Intangible Assets - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Apr. 30, 2013	Apr. 30, 2013
Goodwill And Other Intangible Assets [Line Items]
Third quarter impairment		$ (6,810)
Impairment of goodwill and intangible assets	11,525	11,525
Buses
Goodwill And Other Intangible Assets [Line Items]
Amortizable intangible assets impairment charge		4,715
Fair value in excess of carrying value	15.00%	15.00%
Goodwill fair value	0	0
Third quarter impairment	(6,810)
Impairment of goodwill and intangible assets		$ 11,525

The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value.

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Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

+ References

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