Stock-Based Awards and Programs (Details 3) (Stock Options, USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Stock Options
Stock options
Outstanding, balance at the beginning of the period (in shares)	267,400	232,600
Granted (in shares)		34,800
Exercised (in shares)	77,100
Outstanding, balance at the end of the period (in shares)	190,300	267,400
Exercisable (in shares)	128,500	149,200
Weighted Average Exercise Price
Outstanding, balance at the beginning of the period (in dollars per option)	$ 21.69	$ 22.19
Granted (in dollars per share)		$ 18.36
Exercised (in dollars per share)	$ 22.02
Outstanding, balance at the end of the period (in dollars per option)	$ 21.56	$ 21.69
Exercisable (in dollars per share)	$ 23.15	$ 23.04
Intrinsic value of unexercised options if closing price of stock is less than the exercise price (in dollars per share)	$ 0
Aggregate intrinsic value
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Maximum	$ 0.1	$ 0.1
Weighted-average remaining contractual life of outstanding options (in years)	5.6	6.6
Range of exercise prices, low end of range (in dollars per share)	$ 18.12	$ 18.12
Range of exercise prices, high end of range (in dollars per share)	$ 23.81	$ 23.81
Total unrecognized compensation expense related to non-vested options and related dividend equivalents granted under the plan, maximum	0.1
Total unrecognized compensation expense related to non-vested options and related dividend equivalents granted under the plan		$ 0.3
Recognition period, low end of range (in years)	0.5	1
Recognition period, high end of range (in years)	1.5	3