Debt - Schedule of Debt (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) community	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Total		$ 5,142,291	$ 6,045,167
Less current portion		602,501	215,255
Total long-term debt and capital and financing lease obligations, less current portion		4,539,790	5,829,912
Debt discount and deferred financing costs		22,954
Mortgage notes payable due 2018-2047
Debt Instrument [Line Items]
Total		$ 3,497,762	$ 3,184,229
Weighted average interest rate		4.59%	4.50%
Debt discount and deferred financing costs		$ 16,600	$ 4,500
Capital and Financing Lease Obligations
Debt Instrument [Line Items]
Total		$ 1,271,554	$ 2,485,520
Weighted average interest rate		6.75%	8.08%
Debt discount and deferred financing costs		$ 0
Convertible notes payable
Debt Instrument [Line Items]
Total		$ 309,853	$ 295,397
Weighted average interest rate		2.75%
Debt discount and deferred financing costs		$ 6,400	20,900
Principal Amount		316,300
Construction financing due 2032
Debt Instrument [Line Items]
Total		0	$ 3,644
Weighted average interest rate			8.00%
Other notes payable
Debt Instrument [Line Items]
Total		$ 63,122	$ 76,377
Weighted average interest rate		5.98%	5.33%
Forecast | Capital and Financing Lease Obligations
Debt Instrument [Line Items]
Total	$ 374,500
Number of communities | community	20
Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations | 15 Communities Held For Sale | Long-term Debt
Debt Instrument [Line Items]
Long term mortgage debt		$ 30,100	$ 60,500