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Investments (Schedule Of Carrying Amount And Maximum Loss Exposure Of Equity Investments) (Details) - LB Pipe JV [Member] - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
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Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | $ 6,008 | $ 6,241
LB Pipe JV equity method investment [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | 3,902 | 5,246
Loan receivable [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | 1,235 |
Net investment in direct financing lease [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | $ 871 | $ 995

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