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Consolidated Condensed Balance Sheets (Parenthetical) (USD $)
In Thousands, unless otherwise specified |
Mar. 31, 2012
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Dec. 31, 2011
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| Consolidated Condensed Balance Sheets [Abstract] | ||
| Allowance for bad debts | $ 1,724 | $ 1,544 |
| Accumulated depreciation and amortization on property, plant and equipment | $ 993,410 | $ 970,276 |
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- Definition
The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
A valuation allowance relating to a written agreement to receive money (at a specified future date(s) within one year from the reporting date (or the normal operating cycle, whichever is longer), consisting of principal as well as any accrued interest) for the portion that is expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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