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Investments (Schedule Of Carrying Amount And Maximum Loss Exposure Of Equity Investments) (Details) - USD ($) $ in Thousands | Mar. 31, 2016 | Dec. 31, 2015
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LB Pipe & Coupling Products, LLC [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | $ 6,531 | $ 6,241
LB Pipe JV equity method investment [Member] | LB Pipe & Coupling Products, LLC [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | 4,996 | 5,246
Loan receivable [Member] | LB Pipe & Coupling Products, LLC [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | 575 | 0
Net investment in direct financing lease [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | $ 960 | $ 995

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