Debt - Schedule of Credit Facilities (Details) - Homes Segment - Line of Credit	Sep. 30, 2020 USD ($)
Debt Instrument [Line Items]
Maximum Borrowing Capacity	$ 1,500,000,000
Goldman Sachs Bank USA | Final Maturity Date, April 20, 2022
Debt Instrument [Line Items]
Maximum Borrowing Capacity	$ 500,000,000
Weighted Average Interest Rate	3.15%
Citibank, N.A. | Final Maturity Date, January 31, 2022
Debt Instrument [Line Items]
Maximum Borrowing Capacity	$ 500,000,000
Weighted Average Interest Rate	3.67%
Credit Suisse AG, Cayman Islands | Final Maturity Date, July 31, 2021
Debt Instrument [Line Items]
Maximum Borrowing Capacity	$ 500,000,000
Weighted Average Interest Rate	3.97%