Accounting Policies (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 986,519
Operating lease liability	$ 1,041,141
Third-Party Payor Risk | Accounts Receivable
Concentration Risk [Line Items]
Percentage of concentration risk	15.00%	16.00%
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets			$ 1,015,000
Operating lease liability			$ 1,057,000