Share-Based Compensation Arrangements (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended												1 Months Ended
	Dec. 31, 2010 Stock Appreciation Rights (SARs) [Member]	Dec. 31, 2013 Phantom Share Units (PSUs) [Member]	Dec. 31, 2012 Phantom Share Units (PSUs) [Member]	Dec. 31, 2011 Phantom Share Units (PSUs) [Member]	Dec. 31, 2013 Stock Appreciation Rights And Phantom Shares [Member]	Dec. 31, 2012 Stock Appreciation Rights And Phantom Shares [Member]	Dec. 31, 2011 Stock Appreciation Rights And Phantom Shares [Member]	Dec. 31, 2010 Stock Appreciation Rights And Phantom Shares [Member]	Dec. 31, 2013 DSUs [Member]	Dec. 31, 2012 DSUs [Member]	Dec. 31, 2013 Common Class A [Member]	Dec. 31, 2012 Common Class A [Member]	Jan. 20, 2014 Subsequent Event [Member] DSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested Period				3 years
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	7 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		33.33%						33.33%
Common stock price											$ 9.05	$ 4.62
Allocated Share-based Compensation Expense					$ 2.3	$ 2.6	$ (1.6)		$ 0.8	$ 0.5
Share based compensation, unrecognized liability		1.7	0.8
Cash paid for SARs and Phantom Shares					1.6	0.1			0.2	0			0.7
Other Deferred Compensation Arrangements, Liability, Current									$ 1.2	$ 0.6
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period		23,642	435,866	0