Commitments And Contingencies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Rent expense	$ 66.0	$ 61.1	$ 61.6
Letters of credit outstanding amount	27.9
Guarantee	1.5
Purchase Commitments	17.3
HRM Performance Bond Obligations [Member]
Guarantee	30.0
Liability of obligations	1.0
Letter Of Credits Expiration for the Current Year [Member]
Letters of credit outstanding amount	12.6
Letters of Credit Expiration for the Preceding One to Three Years [Member]
Letters of credit outstanding amount	4.7
Letters Of Credit Expiration After Three Years [Member]
Letters of credit outstanding amount	$ 10.6