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Acquisitions (Summary Of The Allocation Of The Purchase Price Of Acquisitions) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2011
Business Acquisition [Line Items]
Goodwill	$ 144,325us-gaap_Goodwill	$ 146,520us-gaap_Goodwill	$ 147,258us-gaap_Goodwill
Privately-Held Companies [Member]
Business Acquisition [Line Items]
Net tangible assets acquired			9,563
Amortizable intangible assets			24,136
Deferred tax liability			(7,899)
Goodwill			16,524
Total			42,324
AWR Corporation [Member]
Business Acquisition [Line Items]
Net tangible assets acquired				10,718
Amortizable intangible assets				31,685
Deferred tax liability				(8,387)
Goodwill				32,379
Total				$ 66,395