Guarantees - Additional Information (Detail) $ in Millions	Sep. 30, 2017 USD ($)
Guarantor Obligations [Line Items]
Guarantee Obligations Maximum Potential Payment	$ 248.9
Carrying amount of guarantees recorded in the consolidated balance sheet	25.5
Property Lease Guarantee [Member]
Guarantor Obligations [Line Items]
Guarantee Obligations Maximum Potential Payment	103.4
Capital Leased Assets, Noncurrent, Fair Value Disclosure	118.9
Carrying amount of guarantees recorded in the consolidated balance sheet	0.0
Standby Letters of Credit [Member]
Guarantor Obligations [Line Items]
Guarantee Obligations Maximum Potential Payment	71.7
Carrying amount of guarantees recorded in the consolidated balance sheet	0.0
Commercial customer financing arrangements
Guarantor Obligations [Line Items]
Guarantee Obligations Maximum Potential Payment	73.8
Carrying amount of guarantees recorded in the consolidated balance sheet	$ 25.5

Fair value portion of the lessor's net investment in nonoperating or leveraged leases expected to be realized or consumed after one year or normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19190-110258

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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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

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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- Details

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- Details

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