Stock Based Compensation - Deferred Share Units and Stock Appreciation Rights Table (Details)	3 Months Ended
	Mar. 31, 2013
Deferred Share Units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
As of December 31, 2012	388,059
Grants	112,654
Exercises	0
As of March 31, 2013	500,713
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
As of December 31, 2012	1,079,000
Grants	1,940,000
Exercises	0
Canceled	(87,000)
As of March 31, 2013	2,932,000