Financial Instruments (Details 5) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Future minimum lease payments under capital leases
2013	1.5
2014	1.3
2015	1.4
2016	1.4
2017	1.4
Thereafter	4.0
Total	11.0
Less amount representing interest (at rates ranging from 4.2% to 8.7%)	1.2
Present value of net minimum capital lease payments	9.8
Less current installments of obligations under capital leases	1.2
Obligations under capital leases, excluding current installments	8.6
Future minimum lease payments under operating leases
2013	9.5
2014	7.4
2015	5.2
2016	2.5
2017	0.7
Thereafter	2.3
Total	27.6
Minimum
Capital Leases
Interest rate for capital leases (as a percent)	4.20%
Maximum
Capital Leases
Interest rate for capital leases (as a percent)	8.70%

Name:	us-gaap_CapitalLeasedAssetsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid within one year (or one operating cycle, if longer) of the balance sheet date.