Debt (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Debt Disclosure [Abstract]
Debt payable within one year	$ 86.2	$ 83.4
Debt payable after one year	7.4	13.4
Debt Subject to Compromise
Bank borrowings	500.0	500.0
Accrued interest on bank borrowings	460.1	437.2
Drawn letters of credit	26.7	26.5
Accrued interest on drawn letters of credit	10.7	9.6
Debt Subject to Compromise	$ 997.5	$ 973.3
Weighted average interest rates on total debt (as a percent)	3.50%	3.50%