Income Taxes Reconciliation of Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Effective Income Tax Rate [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate	35.00%	35.00%	35.00%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes	6.50%	5.30%	5.70%
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential	3.50%	1.00%	1.90%
Effective Income Tax Rate Reconciliation, Permanent Differences	3.20%	0.70%	1.60%
Effective Income Tax Rate Reconciliation, Rate Benefit as an LLC	(4.20%)	(9.30%)	(11.00%)
Effective Income Tax Rate Reconciliation, Tax Settlements	0.10%	(0.60%)	(1.70%)
Effective Income Tax Rate Reconciliation, US Benefit on Foreign Deferred Taxes	(0.90%)	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Other Adjustments	0.00%	(0.30%)	0.00%
Effective Income Tax Rate, Continuing Operations	43.20%	31.80%	31.50%