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Investments (Schedule Of Carrying Amount And Maximum Loss Exposure Of Equity Investments) (Details) - LB Pipe & Coupling Products, LLC [Member] - USD ($) $ in Thousands | Jun. 30, 2015 | Dec. 31, 2014
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Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | $ 6,712 | $ 6,863
LB Pipe JV equity method investment [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | 5,659 | 5,746
Net investment in direct financing lease [Member] |  |
Schedule of Equity Method Investments [Line Items] |  |
Maximum exposure to loss | $ 1,053 | $ 1,117

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