Shareholders' Equity - Treasury Stock (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		35 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2015	May 02, 2012
Equity [Abstract]
Number of shares authorized to be repurchased					5,000,000
Number shares repurchased	157,101		2,800,000
Payments for repurchase of common stock	$ 0.7	$ 0	$ 12.2
Remaining number of shares authorized to be repurchased	2,200,000		2,200,000	2,200,000
Average price per share of treasury stock acquired and held				$ 9.75
Movement in Treasury Stock [Roll Forward]
Beginning balance (in shares)	627,796
Purchases (shares)	157,101		2,800,000
Exercise of stock options (in shares)	0
Restricted stock grants	(690,662)
Forfeitures and other	133,799
Ending balance (in shares)	228,034		228,034	228,034