Schedule of Changes in Product Warranty Liabilities for Continuing Operations (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2017	Jan. 31, 2016
Product Warranty
Beginning balance	$ 208,988	$ 107,847	$ 201,840	$ 108,206
Provision	44,149	25,283	96,096	51,516
Payments	(43,964)	(26,870)	(88,763)	(53,462)
Ending balance	$ 209,173	$ 106,260	$ 209,173	$ 106,260

No definition available.

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- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability that is expected to be paid within one year or the normal operating cycle, if longer. Does not include the balance for the extended product warranty liability.

+ References

No definition available.

+ Details

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- Definition

Amount of decrease in the standard product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard product warranty. Excludes extended product warranties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(2))
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

+ Details

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- Definition

Amount of increase in the standard product warranty accrual from warranties issued. Excludes extended product warranties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph ((c)(3))
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

+ Details

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