Subsequent Events (Details)	1 Months Ended	2 Months Ended	12 Months Ended
	Jun. 30, 2014 community	Feb. 25, 2016 USD ($) community home	Dec. 31, 2015 USD ($) community home Claim building	Dec. 31, 2014 USD ($) home	Dec. 31, 2013 USD ($) home
Subsequent events
Notional balance				$ 215,000,000
Number of apartment homes sold | home				1,337	3,299
Proceeds from sale of real estate			$ 282,163,000	$ 281,125,000	$ 919,442,000
Estimated number of apartment homes in communities to be developed | home			9,634
Number of residential buildings | community			259
Number of apartment homes included in operating apartment communities owned | home			75,584
Number of Apartment Communities Sold | community	8
Casualty (gain) loss and impairment loss, net			$ (10,542,000)	0	$ 0
US Fund
Subsequent events
Debt outstanding			373,863,000
MVPI LLC
Subsequent events
Receipts from a joint venture partner for modification of agreement			21,340,000
Fund II
Subsequent events
Debt outstanding			$ 286,543,000
Number of Apartment Communities Sold | community			4
Avalon at Edgewater
Subsequent events
Number of residential buildings | building			2
Number of uninhabitable residential buildings due to fire damage | building			1
Number of uninhabitable homes | home			240
Number of apartment homes included in operating apartment communities owned | home			168
Loss Contingency New Class Action Claims Filed Number | Claim			4
Insurance Proceeds			$ 44,142,000
Casualty (gain) loss and impairment loss, net			(15,538,000)
Subsequent event
Subsequent events
Number of Communities Acquired | community		2
Number of Apartment Communities Sold | community		2
Subsequent event | Archstone Boca Town Center [Member] | US Fund
Subsequent events
Number of apartment homes sold | home		252
Proceeds from sale of real estate		$ 56,300,000
Subsequent event | Avalon at Edgewater
Subsequent events
Insurance Proceeds		73,008,000
Casualty (gain) loss and impairment loss, net		$ (29,008,000)
Subsequent event | Avalon Kips Bay [Member] | US Fund
Subsequent events
Number of apartment homes sold | home		209
Proceeds from sale of real estate		$ 173,000,000
Subsequent event | Eaves Rancho San Diego [Member] | Fund II
Subsequent events
Number of apartment homes sold | home		676
Proceeds from sale of real estate		$ 158,000,000
Secured notes
Subsequent events
Fixed rate notes			$ 1,561,109,000	$ 2,400,677,000
Secured notes | MVPI LLC
Subsequent events
Fixed rate (as a percent)			3.24%
Line of Credit [Member]
Subsequent events
Line of Credit Facility, Commitment Fee Percentage			0.15%
Line of Credit Facility, Maximum Borrowing Capacity			$ 1,300,000,000
Line of Credit Facility, Commitment Fee Amount			1,950,000
Line of Credit [Member] | Subsequent event
Subsequent events
Debt instrument, basis spread on variable rate (as a percent)		0.825%
Percent of Credit Facility Available to Competitive Bid Option		65.00%
Line of Credit Facility, Commitment Fee Percentage		0.125%
Line of Credit Facility, Maximum Borrowing Capacity		$ 1,500,000,000
Line of Credit, Facility Potential Term Extension Period		9 months
Line of Credit Facility, Commitment Fee Amount		$ 1,875,000
Extension fee		$ 1,500,000
Avalon Hoboken [Member] | Subsequent event
Subsequent events
Number of Apartment Homes, Acquired | home		217
Business Combination, Consideration Transferred		$ 129,700,000
Avalon Hoboken [Member] | Secured notes | Subsequent event
Subsequent events
Fixed rate notes		$ 67,904,000
Fixed rate (as a percent)		4.18%
Avalon Potomac Yards [Member] | Subsequent event
Subsequent events
Number of Apartment Homes, Acquired | home		323
Business Combination, Consideration Transferred		$ 108,250,000
Minimum [Member] | Line of Credit [Member] | Subsequent event
Subsequent events
Debt instrument, basis spread on variable rate (as a percent)		0.80%
Maximum [Member] | Line of Credit [Member] | Subsequent event
Subsequent events
Debt instrument, basis spread on variable rate (as a percent)		1.55%
Cash Flow Hedges Interest Rate Caps | Interest Rate Swap [Member]
Subsequent events
Notional balance			$ 600,000,000
Cash Flow Hedges Interest Rate Caps | Interest Rate Swap [Member] | Subsequent event
Subsequent events
Notional balance		$ 450,000,000
LIBOR | Line of Credit [Member] | Subsequent event
Subsequent events
Debt instrument variable rate (as a percent)		LIBOR