Business acquisition contingent consideration, key assumptions, discount rate.

No definition available.

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- Definition

Percentage Of Ownership Interest

+ References

No definition available.

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- Definition

Retention rate.

+ References

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e1043-128460

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
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Balance Type:	credit
Period Type:	duration

- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The amount of inventory recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
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-SubTopic 10
-Section 55
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Balance Type:	debit
Period Type:	instant

- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

+ References

+ Details

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Balance Type:	debit
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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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- Definition

Percentage of assumed long-term growth in revenues, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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Acquisitions - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015	May 06, 2017
Business Acquisition [Line Items]
Goodwill (Note 12)	$ 2,626.0	$ 2,478.4	$ 2,487.4
Estimated Income tax rate	35.00%
Cash consideration	$ 304.7		1,309.9
FGL [Member]
Business Acquisition [Line Items]
Percentage Of Ownership Interest	80.40%			50.00%
HGI
Business Acquisition [Line Items]
Acquisition related charges	$ 0.0	$ 0.2	$ 0.4
Technology Assets [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Amortization period, intangible asset	4 years
Technology Assets [Member] \| Maximum
Business Acquisition [Line Items]
Amortization period, intangible asset	18 years
Customer Relationships [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Amortization period, intangible asset	2 years
Customer Relationships [Member] \| Maximum
Business Acquisition [Line Items]
Amortization period, intangible asset	20 years
Petmatrix LLC [Member]
Business Acquisition [Line Items]
Goodwill (Note 12)	$ 0.8
Property, plant and equipment	0.9
Goodwill (Note 12)	123.8
Inventory	16.0
Business Combination, Consideration Transferred	255.2
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	$ 255.2
Petmatrix LLC [Member] \| Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	16 years
Estimated Income tax rate	35.00%
Goodwill (Note 12)	$ 12.0
Business Acquisition Contingent Consideration Key Assumptions Discount Rate	12.00%
Petmatrix LLC [Member] \| Customer Relationships [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate	2.00%
Petmatrix LLC [Member] \| Customer Relationships [Member] \| Maximum
Business Acquisition [Line Items]
Fair Value Inputs, Long-term Revenue Growth Rate	20.00%
Retention Rate	98.00%
Petmatrix LLC [Member] \| Tradenames Trademarks And Patents [Member]
Business Acquisition [Line Items]
Goodwill (Note 12)	$ 75.0
GloFish [Member]
Business Acquisition [Line Items]
Goodwill (Note 12)	11.2
Property, plant and equipment	0.6
Goodwill (Note 12)	37.8
Business Combination, Consideration Transferred	49.7
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net	$ 49.7
GloFish [Member] \| Customer Relationships [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years
Estimated Income tax rate	35.00%
Goodwill (Note 12)	$ 1.5
Business Acquisition Contingent Consideration Key Assumptions Discount Rate	12.00%
GloFish [Member] \| Tradenames Trademarks And Patents [Member]
Business Acquisition [Line Items]
Goodwill (Note 12)	$ 6.1