Employee Benefit Plans (Details 4) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Defined Benefit Pension Plan [Member]
Expected payment of future benefits
2013	$ 1.8
2014	2.1
2015	2.3
2016	2.5
2017	2.8
2018 through 2022	17.5
Supplementary Pension Plan [Member]
Expected payment of future benefits
2013	0.4
2014	0.4
2015	0.4
2016	0.5
2017	0.7
2018 through 2022	$ 4.0