Segment and Geographic Information - Identifiable Assets Table (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Identifiable assets:
Identifiable assets	$ 930.0	$ 956.8
United States
Identifiable assets:
Identifiable assets	829.7	844.8
Canada
Identifiable assets:
Identifiable assets	$ 100.3	$ 112.0