Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current assets:
Allowance for uncollectible accounts	$ 6,121	$ 5,152
Shareholders' equity:
Common stock, par value
Common stock, shares authorized	240,000	240,000
Common stock, shares issued	105,794	105,763

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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