Shareholders' Equity - Treasury Stock (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended		26 Months Ended
	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Jun. 30, 2014	May 02, 2012
Equity [Abstract]
Number of shares authorized to be repurchased					5,000,000
Stock repurchased during period, shares	500,000			2,600,000
Payments for repurchase of common stock	$ 1.6	$ 2.5	$ 2.5	$ 11.5
Remaining number of shares authorized to be repurchased	2,400,000	2,400,000
Average price per share of treasury stock acquired and held		$ 13.41
Movement in Treasury Stock [Roll Forward]
Balance as of December 31, 2013 (shares)		1,121,926
Purchases (shares)		760,268
Exercise of stock options (shares)		(87,569)
Restricted stock grants, forfeitures and other (shares)		(697,847)
401(k) matching contribution (shares)		(360,803)
Balance as of September 30, 2014 (shares)	735,975	735,975