v3.7.0.1

Debt - Carrying Value of Debt (Detail) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Short-term debt:
Other short-term debt	$ 1.0	$ 0.7
Total short-term debt	1.0	0.7
Long-term debt:
Registered Notes	600.0	600.0
Other long-term debt (various interest rates)		0.4
Total	1,844.8	1,866.7
Current maturities	(13.1)	(13.3)
Unamortized debt issuance costs	(16.9)	(19.6)
Unamortized discount on term loans	(5.6)	(6.7)
Total long-term debt	1,809.2	1,827.1
USD Term Loan [Member]
Long-term debt:
Term loan	1,011.5	1,022.2
Unamortized debt issuance costs	(7.6)	(9.1)
Unamortized discount on term loans	(4.7)	(5.6)
Euro Term Loan [Member]
Long-term debt:
Term loan	233.3	244.1
Unamortized debt issuance costs	(0.1)	(0.1)
Unamortized discount on term loans	$ (0.9)	$ (1.1)

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts 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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Carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Amount of long-term debt classified as other.

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Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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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.

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Carrying value as of the balance sheet date of uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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