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Schedule II - Valuation and Qualifying Accounts (Tables) | 12 Months Ended
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Dec. 31, 2012
Valuation and Qualifying Accounts [Abstract] |
Schedule Of Valuation And Qualifying Accounts |
(In thousands) | Balance at Beginning of Period |  | Charged to Costs and Expenses |  | Write-offs (Recoveries) of Doubtful Accounts |  | Balance at End of Period
Year ended December 31, 2012: |  |  |  |  |  |  |
Allowance for doubtful accounts | $ | 10,154 |  |  | $ | 478 |  |  | $ | 104 |  |  | $ | 10,528 |
Year ended December 31, 2011: |  |  |  |  |  |  |
Allowance for doubtful accounts | $ | 9,484 |  |  | $ | 633 |  |  | $ | (37 | ) |  | $ | 10,154 |
Year ended December 31, 2010: |  |  |  |  |  |  |
Allowance for doubtful accounts | $ | 9,167 |  |  | $ | 1,047 |  |  | $ | 730 |  |  | $ | 9,484 |

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- Definition Tabular disclosure of allowance and reserve accounts including their beginning and ending balances, as well as a reconciliation by type of activity during the period. + References No definition available. + Details
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