Share-Based Payments (General Descriptions) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended						6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 Common Class A [Member]	Dec. 31, 2013 Common Class A [Member]	Jun. 20, 2008 Common Class A [Member]	Jun. 25, 2004 Common Class A [Member]	Jun. 30, 2014 Director [Member]	Jun. 30, 2014 Employees [Member]	Jun. 25, 2004 1995 Plan [Member] Common Class A [Member]	Jun. 20, 2008 2008 Plan [Member] Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value					$ 1	$ 1	$ 1.00	$ 1.00
Share-based payments, number of shares authorized under plans											300,000	300,000
Annual vesting percentage									20.00%	20.00%
Requisite service period of awards									1 year	3 years
Expiration period of awards			10 years
Period in force, from which option holders may elect to sell back acquired shares			90 days
Pre-tax compensation cost (benefit) recognized	$ 0.8	$ 1.5	$ 2.5	$ 3.0
Compensation cost (benefit), tax expense (benefit)	0.3	0.5	0.8	1.0
Compensation cost related to nonvested options not yet recognized	$ 3.1		$ 3.1
Weighted average period over which the compensation is expected to be recognized			2 years 4 months 24 days