Earnings (Loss) Per Common Share (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended	3 Months Ended
	Jun. 30, 2014 Warrants [Member]	Jun. 30, 2013 Warrants [Member]	Jun. 30, 2014 Warrants [Member]	Jun. 30, 2013 Warrants [Member]	Jun. 30, 2014 Employee Stock Option [Member]	Jun. 30, 2013 Employee Stock Option [Member]	Jun. 30, 2014 Employee Stock Option [Member]	Jun. 30, 2013 Employee Stock Option [Member]	Jun. 30, 2014 Redeemable Convertible Preferred Shares [Member]	Jun. 30, 2013 Redeemable Convertible Preferred Shares [Member]	Jun. 30, 2014 Redeemable Convertible Preferred Shares [Member]	Jun. 30, 2013 3.75% Convertible Senior Subordinated Notes Due April 15, 2014 [Member]	Dec. 31, 2013 3.75% Convertible Senior Subordinated Notes Due April 15, 2014 [Member]	Jun. 30, 2014 3.875% Convertible Senior Debentures, due November 1, 2029 [Member]	Dec. 31, 2013 3.875% Convertible Senior Debentures, due November 1, 2029 [Member]
Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share amount	4,000,000	4,000,000	4,000,000	4,000,000	1,581,700	825,400	773,000	1,748,600	4,162,200	4,162,200	4,162,200	4,557,339
Exercise price	$ 33.33	$ 33.33	$ 33.33	$ 33.33
Convertible notes interest rate													3.75%	3.875%	3.875%