Contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.22(a)(1))
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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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-Topic 942
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-Section S99
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-Section 02
-Paragraph 20, 22
-Article 5

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Debt Schedule (Detail) - USD ($) $ in Millions	12 Months Ended
Debt Schedule (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument
Non-current Portion of Long-term Debt		$ 2,475.1		$ 2,628.7
Current Maturities of Long-term Debt		352.4		151.9
Long-term Debt		2,827.5		2,780.6
Fair Value Hedge Adjustment, LT Debt
Debt Instrument
Non-current Portion of Long-term Debt		(2.7)		(0.2)
Current Maturities of Long-term Debt		2.4		0.0
Secured Notes Issued in 2007 \| Senior Notes
Debt Instrument
Non-current Portion of Long-term Debt		324.0		398.4
Year of Maturity	Dec. 31, 2037
Interest Rate Terms	Variable
Notes Issued in 1998 with 2018 Maturity Date \| Senior Notes
Debt Instrument
Non-current Portion of Long-term Debt		200.0		200.0
Year of Maturity	Dec. 31, 2018
Stated Interest Rate of Debt			7.00%
Notes Issued in 1998 with 2028 Maturity Date \| Senior Notes
Debt Instrument
Non-current Portion of Long-term Debt		365.8		365.8
Year of Maturity	Dec. 31, 2028
Notes Issued in 1998 with 2028 Maturity Date \| Minimum \| Senior Notes
Debt Instrument
Stated Interest Rate of Debt			6.75%
Notes Issued in 1998 with 2028 Maturity Date \| Maximum \| Senior Notes
Debt Instrument
Stated Interest Rate of Debt			7.25%
Notes Issued in 2002 \| Senior Notes
Debt Instrument
Non-current Portion of Long-term Debt		39.5		39.5
Year of Maturity	Dec. 31, 2032
Stated Interest Rate of Debt			7.375%
Notes Issued in 2009
Debt Instrument
Current Maturities of Long-term Debt		350.0		0.0
Year of Maturity	Dec. 31, 2016
Stated Interest Rate of Debt			7.125%
Notes Issued in 2009 \| Senior Notes
Debt Instrument
Non-current Portion of Long-term Debt		0.0		350.0
Year of Maturity	Dec. 31, 2016
Stated Interest Rate of Debt			7.125%
Notes Issued in 2010 \| Senior Notes
Debt Instrument
Non-current Portion of Long-term Debt		399.8		399.7
Year of Maturity	Dec. 31, 2020
Stated Interest Rate of Debt			5.625%
Notes Issued in 2012 \| Senior Notes
Debt Instrument
Non-current Portion of Long-term Debt		248.7		248.7
Year of Maturity	Dec. 31, 2042
Stated Interest Rate of Debt			5.75%
Notes Issued in 2014 \| Senior Notes
Debt Instrument
Non-current Portion of Long-term Debt		349.5		349.5
Year of Maturity	Dec. 31, 2024
Stated Interest Rate of Debt			4.00%
Notes Issued in 2015 \| Senior Notes
Debt Instrument
Non-current Portion of Long-term Debt		273.2		0.0
Year of Maturity	Dec. 31, 2025
Stated Interest Rate of Debt			3.875%
Notes Issued 1990 to 1996 \| Medium-term Notes
Debt Instrument
Non-current Portion of Long-term Debt		50.8		50.8
Debt Instrument, Maturity Date Range, Start	Dec. 31, 2023
Debt Instrument, Maturity Date Range, End	Dec. 31, 2028
Notes Issued 1990 to 1996 \| Minimum \| Medium-term Notes
Debt Instrument
Stated Interest Rate of Debt			7.00%
Notes Issued 1990 to 1996 \| Maximum \| Medium-term Notes
Debt Instrument
Stated Interest Rate of Debt			7.19%
Notes Issued in 1998 with 2038 Maturity Date \| Junior Subordinated Debt
Debt Instrument
Non-current Portion of Long-term Debt		226.5		226.5
Year of Maturity	Dec. 31, 2038
Stated Interest Rate of Debt	7.405%		7.405%
Notes Issued in 2005
Debt Instrument
Current Maturities of Long-term Debt		$ 0.0		$ 151.9
Year of Maturity	Dec. 31, 2015
Stated Interest Rate of Debt			6.85%