Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Allowance for uncollectible accounts	$ 4,735	$ 2,234
Shareholders' equity:
Common stock, par value
Common stock, shares authorized	240,000,000us-gaap_CommonStockSharesAuthorized	240,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	105,586,000us-gaap_CommonStockSharesIssued	105,640,000us-gaap_CommonStockSharesIssued

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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