Subsequent Events (Details Textual) (USD $) In Millions, except Share data	Jul. 18, 2011	Jul. 19, 2011 706-home community [Member]
Business Acquisition [Line Items]
Acquisition Cost		$ 443.4
Public offering of common stock	20,700,000
Public offering common stock underwriters' exercise of overallotment option in full at closing	2,700,000
Price per share of public offering of Common Stock	$ 25.00
Net proceeds of Public offering after underwriting discounts and commissions and estimated offering expenses	$ 496.3

Net proceeds of Public offering after underwriting discounts and commissions and estimated offering expenses.

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- Definition

Price per share of public offering of Common Stock.

+ Details

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- Definition

Public offering common stock underwriters' exercise of overallotment option in full at closing.

+ Details

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- Definition

Public offering of common stock.

+ Details

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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)
-Number 141
-Paragraph 51
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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