Earnings Per Common Share Earnings Per Share Footnote (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2014	Aug. 31, 2009
Class of Warrant or Right [Line Items]
Shares issued on conversion of warrants	0
Warrants on Senior Exchangeable Notes due 2012 [Member]
Class of Warrant or Right [Line Items]
Beginning date for maturity of warrants	Jan. 15, 2013
Ending date for maturity of warrants	Mar. 27, 2013
Shares issued on conversion of warrants	2,135,221
Warrants on Senior Exchangeable Notes due 2015 [Member]
Class of Warrant or Right [Line Items]
Strike price of warrants		28.12
Senior Exchangeable Notes due 2015 - Settlements 1, 2 and 3 [Member]
Class of Warrant or Right [Line Items]
Redemption amount settled	41,500,000
Senior Exchangeable Notes due 2015 at a fixed interest rate of 4.50% [Member]
Class of Warrant or Right [Line Items]
Face amount	130,973,000	$ 130,973,000	$ 172,500,000.0
Strike price of warrants		28.12