Estimated Fair Values of Financial Instruments (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010	Jun. 30, 2010	Jun. 30, 2009	Jun. 30, 2008
Financial assets
Cash and cash equivalents	$ 744.0	$ 809.5	$ 500.7	$ 357.5	$ 253.7
Receivables	483.4	411.4	305.4
Non-current investments	272.2	344.3	254.3
Financial liabilities
Long-term loans	1,360.7	1,136.6	430.0
Accounts payable and provisions	669.9	670.6	551.9
Interest payable	11.2	4.1	4.5
Short-term loans and current portion of long-term loans	547.0	261.7	691.1
Other non-current liabilities	13.5	19.7
Carrying value
Financial assets
Cash and cash equivalents	744.0	809.5	500.7
Receivables	483.4	411.4	305.4
Non-current investments	272.2	344.3	254.3
Financial liabilities
Long-term loans	1,360.7	1,136.6	430.0
Accounts payable and provisions	669.9	670.6	551.9
Interest payable	11.2	4.1	4.5
Short-term loans and current portion of long-term loans	547.0	261.7	691.1
Other non-current liabilities	13.5	19.7
Fair value
Financial assets
Cash and cash equivalents	744.0	809.5	500.7
Receivables	483.4	411.4	305.4
Non-current investments	272.2	344.3	254.3
Financial liabilities
Long-term loans	1,263.0	1,107.5	430.0
Accounts payable and provisions	669.9	670.6	551.9
Interest payable	11.2	4.1	4.5
Short-term loans and current portion of long-term loans	547.0	261.2	691.1
Other non-current liabilities	$ 13.5	$ 19.7

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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