Share Repurchase Program (Details) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	2 Months Ended	12 Months Ended
	Oct. 29, 2012	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Equity, Class of Treasury Stock [Line Items]
Stock repurchase program, authorized amount	$ 60.0
Stock repurchase program, remaining authorized repurchase amount			$ 56.2
Stock repurchased and retired during period, shares		137,262		0	0
Stock repurchased and retired during period, average amount per share		$ 27.34