Accrued Expenses and Other Current Liabilities and Other Liabilities - Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accrued Expenses and Other Current Liabilities and Other Liabilities
Patient prepayments, deposits, and refunds payable	$ 26,969	$ 24,183
Accrued sales taxes and other taxes	10,240	8,543
Insurance and self-insurance accruals	7,786	8,033
Derivative liability	7,704	3,516
Liabilities incurred to seller in acquisitions	3,656
Accrued professional fees	1,547	2,533
Accrued interest payable	747	266
Other current liabilities	13,785	8,751
Total	$ 72,434	$ 55,825