Commitments And Contingencies (Schedule Of Rent Expense Under Operating Leases) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Commitments And Contingencies [Abstract]
Operating leases expense	$ 3,850	$ 3,553	$ 3,631
Purchased water under long-term agreements	11,796	14,507	13,621
Water treatment expense under contractual agreement	$ 897	$ 865	$ 777

Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses.

No definition available.

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Balance Type:	debit
Period Type:	duration