Related Party Transactions (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Agencies	Dec. 31, 2011	Dec. 31, 2010
Director [Member]
Related Party Transaction [Line Items]
Number of Agencies Revenue recorded from (in agencies)	2
Revenue from related parties	$ 1.8	$ 5.1	$ 0.3
Accounts Receivable, Related Parties	2.8	0
Former Board of Director [Member]
Related Party Transaction [Line Items]
Revenue from related parties		0.1	0.2
Board of Director 2 [Member]
Related Party Transaction [Line Items]
Revenue from related parties		$ 0.2