Income Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Effective Income Tax Rate Reconciliation, Percentage
Federal statutory rate	21.00%	35.00%	35.00%
State taxes net of federal tax benefit	3.40%	0.10%	0.20%
Goodwill impairment		(33.90%)
Non-deductible transaction costs			0.70%
Noncontrolling interest	20.40%	0.60%	(16.50%)
Valuation allowance	(17.90%)	29.50%	43.20%
Nondeductible compensation	(13.90%)	(0.10%)	2.20%
Foreign taxes	(1.20%)	(0.10%)	1.30%
Other	2.40%	(0.70%)	1.10%
Tax Act impact		11.80%
Change in state tax rates	(2.00%)		(5.50%)
FIN 48 reversal			(3.70%)
Effective income tax rate, percent	12.20%	42.20%	58.00%