Business Combinations (Textual) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012 Apartments
Business Combinations - Additional Information [Abstract]
Land acquired	$ 58.0
Buildings and improvements acquired	285.6
Furniture, fixtures, and equipment acquired	0.6
Intangibles acquired	0.5
Residential leases at fair value	2.9
Liabilities assumed, senior notes	30.3
Net assets acquired	317.3
Number of real estate units acquired (apartments)	2,452
Acquired properties, purchase price	312.0
Revenue from acquired properties	17.6
Net income from acquired property	$ 3.1

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Buildings and Improvements

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- Definition

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Furniture, Fixtures, and Equipment

+ References

No definition available.

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- Definition

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Land

+ References

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- Definition

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities, Senior Notes

+ References

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- Definition

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Residential Leases, Fair Value

+ References

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- Definition

Number of Units Acquired in Real Estate Property

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 51

-Subparagraph d

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

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- Definition

The net amount recognized as of the acquisition date for the aggregate identifiable assets acquired in excess of or less than the aggregate liabilities assumed.

+ References

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