Significant Accounting Policies and Recent Accounting Pronouncements - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Provision for doubtful accounts	$ 4,078	$ 6,062	$ 1,372
Estimated Useful Life (Yrs)	12 years 3 months 18 days
Accrued transportation costs	$ 87,063	84,889
Deferred financing costs, current, net	33
Deferred financing costs, noncurrent, net		268
Gross reinsurance liability reserve	12,826	10,489
Reimbursable reinsurance reserve	8,493	6,589
Self insurance maximum exposure per claim employee medical	300
Self insurance maximum exposure per claim employee medical, stop-loss limit	400
Self insurance reserve	1,864	2,201
Decrease in cash provided by investing activities	10,858	45,322	7,020
Operating lease assets	20,095	0		$ 23,165
Operating lease, liability	21,232			$ 24,491
Social Services Providers Captive Insurance Company
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gross reinsurance liability reserve	$ 4,333	3,900
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated Useful Life (Yrs)	3 years
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated Useful Life (Yrs)	15 years
Continuing Operations
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Provision for doubtful accounts		$ 338	$ 1,347