Organization and Summary of Significant Accounting Policies (Textual) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013 Communities Property		Dec. 31, 2012	Dec. 31, 2011
Real Estate Properties
General partners' capital account, units outstanding	74,830,726		42,316,398
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest	94.70%		96.10%
Number of apartment communities owned (properties)	270
Number of Real Estate Properties	275
Advertising expenses	$ 9,500,000		$ 8,800,000	$ 8,700,000
Development and capital improvements in progress	166,048,000
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	23,800,000
Finite-Lived Intangible Assets, Amortization Expense, Year Three	3,300,000
Finite-Lived Intangible Assets, Amortization Expense, Year Four	3,300,000
Finite-Lived Intangible Assets, Amortization Expense, Year Five	3,300,000
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	2,600,000
Furniture, fixtures and equipment
Real Estate Properties
Estimated useful lives (years)	5 years
Leases, Acquired-in-Place
Real Estate Properties
Amortization period of in-place leases and residential relationships (months)	6 months
Gross real estate assets	50,300,000		1,600,000	1,800,000
Depreciation and amortization	23,500,000		3,700,000	3,500,000
Accumulated amortization	21,900,000		1,000,000	700,000
Dividend Declared
Real Estate Properties
Accrued expenses and other liabilities	57,700,000		30,600,000	27,000,000
Real Estate Taxes
Real Estate Properties
Accrued expenses and other liabilities	40,400,000		27,900,000	25,400,000
Interest Expense
Real Estate Properties
Accrued expenses and other liabilities	18,100,000		7,500,000	6,300,000
Minimum
Real Estate Properties
Percentage of ownership interests of all consolidated subsidiaries (percent)	95.00%
Minimum | Land improvements and buildings
Real Estate Properties
Estimated useful lives (years)	8 years
Minimum | Computer and software
Real Estate Properties
Estimated useful lives (years)	3 years
Maximum
Real Estate Properties
Percentage of ownership interests of all consolidated subsidiaries (percent)	100.00%
Maximum self insurance reserve for general liability claims	50,000
Maximum self insurance reserve for workers' compensation claims	500,000
Maximum | Land improvements and buildings
Real Estate Properties
Estimated useful lives (years)	40 years
Maximum | Computer and software
Real Estate Properties
Estimated useful lives (years)	5 years
Out Of Period Adjustment
Real Estate Properties
Description of prior period adjustments	In the twelve months ended December 31, 2011, we recorded a $1.8 million non-cash adjustment to general and administrative expenses related to restricted stock grants issued to certain employees. This adjustment was made during the second quarter of 2011. This error correction represents a cumulative adjustment for the 3.5 year period ended June 30, 2011, required by Accounting Standards Codification, or ASC, 718to record expense under certain of our restricted stock grant based incentive plans using liability accounting rather than treating these grants as equity awards.
Development Properties
Real Estate Properties
Number of Real Estate Properties	5
Number of units under development community	1,461
Number of impaired units in a community as a result of purchase offer received and long term considerations (units)	509
Development Properties | Expected Costs
Real Estate Properties
Development and capital improvements in progress	203,000,000
Development Properties | Costs Incurred to Date
Real Estate Properties
Development and capital improvements in progress	134,500,000
Retail
Real Estate Properties
Number of Real Estate Properties	4
Square footage of real estate property (square foot)	105,168
Commercial Properties
Real Estate Properties
Number of Real Estate Properties	4
Square footage of real estate property (square foot)	1,124,596
Mid America Multifamily Fund II, LLC
Real Estate Properties
Equity Method Investment, Ownership Percentage	33.33%
Number Of Units Acquired In Real Estate Property	1,156	[1]
Belterra
Real Estate Properties
Equity Method Investment, Ownership Percentage	10.00%
Number Of Units Acquired In Real Estate Property	288
Colonial Grand at McKinney
Real Estate Properties
Equity Method Investment, Ownership Percentage	25.00%
Number Of Units Acquired In Real Estate Property	0	[2]
Land Title Building
Real Estate Properties
Equity Method Investment, Ownership Percentage	33.30%
Number of Real Estate Properties	1
Interest in real estate joint ventures (percent)	33.33%
Square footage of real estate property (square foot)	29,971
Parent Company [Member]
Real Estate Properties
Total interest capitalized during period	2,089,000		2,318,000	1,156,000
Gross real estate assets	7,603,638,000		3,707,582,000
Depreciation and amortization	186,979,000		121,211,000	106,009,000	[3]
Accumulated amortization	1,124,207,000		1,027,618,000
Accrued expenses and other liabilities	206,190,000		94,719,000
Development and capital improvements in progress	166,048,000		52,455,000
Capitalized Salaries	391,000		274,000	292,000
Capitalized Real Estate Taxes	$ 288,000		$ 276,000	$ 183,000

[1] This joint venture is comprised of four apartment communities.

[2] This joint venture consists of undeveloped land.

[3] The 2011 column shows the segment break down based on the 2012 same store portfolios. A comparison using the 2013 same store portfolio would not be comparative due to the nature of the classifications.