Commitments and Contingencies (Details) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2016 USD ($) single_family_property	Dec. 31, 2015 USD ($) single_family_property
Long-term Purchase Commitment [Line Items]
Single-family properties sales in escrow | single_family_property	445
Single-family properties sales in escrow, selling price | $	$ 26.7
Single Family Properties
Long-term Purchase Commitment [Line Items]
Commitment to acquire single-family properties | single_family_property	103	12
Purchase price of commitment to acquire single-family properties | $	$ 22.4	$ 1.7