Significant Accounting Policies - Additional Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) shares	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) Group visit PeriodicRate shares	Sep. 30, 2017 USD ($)	Apr. 01, 2018 shares	Dec. 31, 2017 shares
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage equity ownership, license leasing arrangements	100.00%
Net service revenue	$ (507,043)	$ (269,678)	$ (1,300,121)	$ (771,462)
Number of Medicare home health resource groups | Group			153
Number of days from date RAP paid to submit final Medicare bill			60 days
Medicare sequestration reduction for episodes beginning after March 31, 2013			2.00%
Low utilization adjustment visits | visit			5
Selected hospice, periodic rate used to calculate revenue | PeriodicRate			1
Number of hospice, periodic rates used to calculate revenue | PeriodicRate			4
Minimum percentage of Medicare reimbursement from inpatient care services that subjects individual programs to inpatient cap			20.00%
Determination period for hospice Medicare inpatient reimbursement cap			12 months
Medicare credit risk for accounts receivable	50.00%		50.00%
Reimbursement for initial episode of care			60.00%
Number of days from start of episode to submit final Medicare bill			120 days
Reimbursement for subsequent episodes of care			50.00%
Common stock, shares authorized | shares	60,000,000		60,000,000		60,000,000	40,000,000
Adjustment for ASU 2014-09 | Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net service revenue	$ 7,100	3,194	$ 19,700	8,238
HCI
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net service revenue	(13,417)	$ 0	$ (23,554)	$ 0
ACO | HCI
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net service revenue related to the 2017 ACO service periods	$ 3,700