Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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Namespace Prefix:	us-gaap_
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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Debt - Debt and Average Interest Rates on Debt Outstanding (Detail) € in Millions, $ in Millions	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 EUR (€)
Debt Instrument [Line Items]
Unamortized Debt Issuance Expense	$ (22.1)	$ (23.5)
Total debt	4,837.8	4,686.5
Current maturities and short-term borrowings	(0.7)	(0.7)
Long-term debt	$ 4,837.1	4,685.8
Commercial Paper
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	1.628%
Total debt	$ 169.4	179.5
Capital Lease Obligations [Member]
Debt Instrument [Line Items]
Total debt		0.7
Other Debt Obligations [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	1.734%
Total debt	$ 0.7
Long Term Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total debt		1,181.4
Senior Notes 1.875% Due 2017 \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	1.875%
Total debt	$ 350.0	$ 350.0
Senior Notes 2.900% Due 2018 \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	2.90%	2.90%	2.90%
Total debt	$ 500.0	$ 500.0
Senior Notes 2.650% Due 2019 \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	2.65%
Total debt	$ 250.0	250.0
Senior Notes 5.000% Due 2021 \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	5.00%
Total debt	$ 500.0	500.0
Senior Notes 3.150% Due 2022 \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	3.15%
Total debt	$ 550.0	$ 550.0
Senior Notes 2.45% Due 2019 \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	2.45%	2.45%	2.45%
Total debt	$ 559.8	$ 548.4	€ 500.0
Senior Notes 3.625% Due 2020 \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	3.625%	3.625%	3.625%
Total debt	$ 400.0	$ 400.0
Senior Notes 4.65% Due 2025 \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	4.65%	4.65%	4.65%
Total debt	$ 250.0	$ 250.0
Subsidiary Issuer
Debt Instrument [Line Items]
Long-term debt	$ 5,509.9	$ 4,535.5
Revolving Credit Facility [Member] \| Long Term Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate	1.936%
Total debt	$ 1,330.0