Acquisitions (Details) (USD $) In Thousands, unless otherwise specified	Jul. 31, 2011 Ohio [Member]	Jun. 30, 2011 Texas [Member]
Acquisitions [Line Items]
Cash paid for business acquisition	$ 88,000	$ 6,245
Liabilities assumed for business acquisition	$ 16,000
Number of customers	57,000	5,300
Number of water systems acquired		51
Number of wastewater systems acquired		5

Fair Value of the liabilities incurred by the acquirer to former owners of the acquiree, including the fair value of any contingent consideration. If liabilities transferred as consideration remain within the combined entity after the business combination (for example, because the assets or liabilities were transferred to the acquiree rather than to its former owners), and the acquirer therefore retains control of them; in that situation, the acquirer measures those liabilities at their carrying amounts immediately before the acquisition date.

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

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-Name Accounting Standards Codification

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-Name Statement of Financial Accounting Standard (FAS)

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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