Acquisitions - Estimated Fair Values of Assets and Liabilities Acquired (Details) - American Residential Properties Inc. - USD ($) $ in Thousands		9 Months Ended
	Feb. 29, 2016	Sep. 30, 2016	Sep. 30, 2015
Business Acquisition [Line Items]
Land	$ 262,396
Buildings and improvements	1,014,857
Cash and cash equivalents	15,499
Restricted cash	9,521
Rent and other receivables	843
Escrow deposits, prepaid expenses and other assets	35,134
In-place leases	22,696
Accounts payable and accrued expenses	(38,485)
Net assets acquired	1,322,461
Total debt assumed or extinguished	792,001
Equity transaction consideration	530,460
Total transaction consideration	1,322,461
Credit facility
Business Acquisition [Line Items]
Total debt assumed or extinguished	350,000	$ 350,000	$ 0
Exchangeable senior notes
Business Acquisition [Line Items]
Total debt assumed or extinguished	112,298	112,298	0
Asset-backed securitization
Business Acquisition [Line Items]
Total debt assumed or extinguished	$ 329,703	$ 329,703	$ 0