Accounts Payable and Provisions (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Short-term Debt [Line Items]
Trade payables	$ 141.2	$ 220.5
Accruals	173.8	352.0
Payroll and other compensation	55.1	57.8
Leave pay accrual	42.9	73.8
Other	15.1	27.6
Accounts payable and provisions	445.0	734.0
South Deep Gold Mine
Short-term Debt [Line Items]
Short-term portion of the South Deep Dividend liability	1.9	2.3
Stamp Duty [Member] \| Yilgarn South
Short-term Debt [Line Items]
Stamp duty due on acquisition of Yilgarn South assets	$ 15.0

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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Carrying value as of the balance sheet date of obligations incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. 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 value as of the balance sheet date of the obligations incurred through that date and payable for employees' services provided. 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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