Long-Term Debt (Schedule of Africa/Asia Pacific credit facilities) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Outstanding borrowings	$ 1,337.4us-gaap_LongTermDebt	$ 1,386.9us-gaap_LongTermDebt
Maturities within one year	403.5
Africa/Asia Pacific [Member] \| Credit Facilities [Member]
Debt Instrument [Line Items]
Outstanding borrowings	47.7	69.7
Undrawn availability	62.0	125.3
Interest rate — weighted average	5.30%	5.10%
Maturity Date	Various	Various
Maturities within one year	$ 47.7

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Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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Weighted average interest rate of debt outstanding.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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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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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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