Inventories - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
Apr. 30, 2019	Feb. 01, 2019	Jul. 31, 2018
Inventories	$ 1,008,537		$ 579,758
Subsidiaries valued inventory in last-in, first-out method	312,757		305,990
Subsidiaries valued inventory in first-in, first-out method	695,780		$ 273,768
Erwin Hymer Group [Member]
Subsidiaries valued inventory in first-in, first-out method		$ 593,053
Erwin Hymer Group [Member] \| FIFO [Member]
Subsidiaries valued inventory in first-in, first-out method	441,081
Change In FIFO Inventory	422,012
Erwin Hymer Group [Member] \| Finished Goods [Member]
Subsidiaries valued inventory in first-in, first-out method	197,356
Change In Inventory Finished Goods	$ 224,271

Amount of Change In FIFO Inventory.

No definition available.

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Balance Type:	debit
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- Definition

Amount of Change In Inventory Finished Goods.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The amount of inventory recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=108330185&loc=d3e2207-128464

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

+ References

+ Details

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- Details

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- Details

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