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Investments (Schedule Of Carrying Amount And Maximum Loss Exposure Of Equity Investments) (Details) - Lb Pipe Coupling Products Llc - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Schedule of Equity Method Investments |  |
Maximum exposure to loss | $ 5,845 | $ 6,008
LB Pipe JV equity method investment |  |
Schedule of Equity Method Investments |  |
Maximum exposure to loss | 3,875 | 3,902
Revolving line of credit |  |
Schedule of Equity Method Investments |  |
Maximum exposure to loss | 1,235 | 1,235
Net investment in direct financing lease |  |
Schedule of Equity Method Investments |  |
Maximum exposure to loss | $ 735 | $ 871

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