Income Taxes - Schedule of Reconciliation of U.S. Statutory Income Tax Rate to Company's Effective Tax Rate (Details) - USD ($) $ in Millions		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
U.S. statutory tax rate		35.00%	35.00%	35.00%
Increase due to state and local taxes, net of federal benefit		2.60%	2.60%	2.60%
Effect of permanent differences		(0.10%)	(0.20%)	1.20%
Income attributable to non-controlling interests		(12.50%)	(14.10%)	(19.70%)
Other		0.20%	1.10%	0.10%
Subtotal		25.20%	24.40%	19.20%
Impact of reduction in TRA liability on non-controlling interests		4.50%
Effect of permanent difference – reduction in TRA liability		(13.60%)
Tax Cuts and Jobs Act rate change		45.10%
Effective tax rate		61.20%	24.40%	19.20%
Income tax expense benefit		$ 40.9
Benefit as a result of reduction in TRA Liability		32.7
Net effect on net income		8.2
Income taxes receivables		$ 0.7
Income taxes payable			$ 0.4
Forecast
U.S. statutory tax rate	21.00%