Estimated Fair Values of Financial Instruments (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financial assets
Cash and cash equivalents	$ 440.0	$ 458.0	$ 325.0	$ 655.6
Receivables	168.9	226.5
Non-current investments	175.0	286.5
Financial liabilities
Long-term loans	1,803.6	1,770.7
Accounts payable and provisions	416.2	498.5
Interest payable	11.4	11.2
Short-term loans and current portion of long-term loans	16.7	140.2
Other non-current liabilities	8.7	9.1
Carrying value
Financial assets
Cash and cash equivalents	440.0	458.0
Receivables	85.2	122.4
Non-current investments	175.0	286.5
Financial liabilities
Long-term loans	1,803.6	1,770.7
Accounts payable and provisions	381.7	460.6
Interest payable	11.4	11.2
Short-term loans and current portion of long-term loans	16.7	140.2
Other non-current liabilities	6.5	9.1
Fair value
Financial assets
Cash and cash equivalents	440.0	458.0
Receivables	85.2	122.4
Non-current investments	180.0	279.9
Financial liabilities
Long-term loans	1,569.8	1,614.4
Accounts payable and provisions	381.7	460.6
Interest payable	11.4	11.2
Short-term loans and current portion of long-term loans	16.7	140.2
Other non-current liabilities	$ 6.5	$ 9.1

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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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.

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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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.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Aggregate carrying amount, as of the balance sheet date, of noncurrent obligations not separately disclosed in the balance sheet. Noncurrent liabilities are expected to be paid after one year (or the normal operating cycle, if longer).

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