Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Concentration Risk by Risk Factor (Details) - Geographic Concentration Risk	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Billed Receivables | Florida
Concentration Risk [Line Items]
Concentration risk, percentage	56.00%	61.00%
Billed Receivables | Indiana
Concentration Risk [Line Items]
Concentration risk, percentage	14.00%	9.00%
Billed Receivables | Texas
Concentration Risk [Line Items]
Concentration risk, percentage	3.00%	4.00%
Revenues Recognized | Florida
Concentration Risk [Line Items]
Concentration risk, percentage	25.00%	24.00%	25.00%
Revenues Recognized | Indiana
Concentration Risk [Line Items]
Concentration risk, percentage	15.00%	14.00%	15.00%
Revenues Recognized | Texas
Concentration Risk [Line Items]
Concentration risk, percentage	12.00%	13.00%	13.00%